ChatGPT

By OpenAI. Documented UTM: utm_source=chatgpt.com (docs).

What works today

OpenAI publishes the utm_source=chatgpt.com value in its publisher FAQ, and ChatGPT adds it to every outbound link we tested on the web: citations, links in the answer text and links the user pasted. It keeps existing query parameters and inserts the tag before a #fragment. After a UI update in early October 2026, the tag was restored within about a week.

As of 2026-10-20.

Status

Rows are tests, columns are surfaces. Select a cell to see each link location, the date, the method and the evidence. Reported means a third-party report we have not yet verified first-hand. See how we test.

Test

Web (desktop)

Web (mobile)

iOS app

Android app

macOS app

Windows app

REF-01 Referrer present

Missing (2026-10-20)

Inline citation in an answer: Missing · 2026-10-20 · Verified (manual) · Chrome 155.0.8059.85 / macOS 27.2. document.referrer: (none) Landing URL: https://www.rfc-editor.org/rfc/rfc9110.html?utm_source=chatgpt.com Clicked the "RFC Editor" citation chip; document.referrer was empty on the landing page. Data
Sources / citations panel, Search result or link cards, Shopping / product cards, Map / place cards, Deep research / research report, Canvas / document / artifact view, Shared conversation page (public share link): Missing · 2026-10-16 · Reported. After the fix, "the referrer is still missing on most ChatGPT clicks" (C. Huesler, via Relevant Audience). Source Data
Link or URL written in answer text: Missing · 2026-10-20 · Verified (manual) · Chrome 155.0.8059.85 / macOS 27.2. document.referrer: (none) Landing URL: https://www.rfc-editor.org/rfc/rfc9110.html?utm_source=chatgpt.com#section-10.1.3 Clicked a link written in the answer text ("Source:" line); document.referrer was empty. Data
Link the user pasted, echoed back: Missing · 2026-10-20 · Verified (manual) · Chrome 155.0.8059.85 / macOS 27.2. document.referrer: (none) Landing URL: https://main--attribution-now--keepthebyte.aem.page/t/mrg-02/openai-chatgpt/web-desktop/pasted-link?utm_source=chatgpt.com#section-2 Clicked the echoed mrg-02 link; document.referrer was empty. Data

Untested

Inline citation in an answer, Sources / citations panel, Search result or link cards, Shopping / product cards, Map / place cards, Deep research / research report, Link or URL written in answer text, Link the user pasted, echoed back, Shared conversation page (public share link): Untested.

Reported: missing (2026-04-21)

All link locations: Missing · 2026-04-21 · Reported. Mobile app passed no referrer (WISLR test, April 12, 2026; iOS and Android reported together). Source Data

Reported: missing (2026-04-21)

All link locations: Missing · 2026-04-21 · Reported. Mobile app passed no referrer (WISLR test, April 12, 2026; iOS and Android reported together). Source Data

Missing (2026-10-20)

Inline citation in an answer: Missing · 2026-10-20 · Verified (manual) · ChatGPT 26.1013.40934 (macOS app) → Chrome 155 / macOS 27.2. Referer: (none) document.referrer: (none) Landing URL: https://attribution.now/t/ref-01/openai-chatgpt/macos/inline-citation?utm_source=chatgpt.com Clicked the "attribution.now +1" citation chip; opened in Chrome with no Referer and Sec-Fetch-Site none. Data
Sources / citations panel: Missing · 2026-10-20 · Verified (manual) · ChatGPT 26.1013.40934 (macOS app) → Chrome 155 / macOS 27.2. Referer: (none) document.referrer: (none) Landing URL: https://attribution.now/t/ref-01/openai-chatgpt/macos/inline-citation?utm_source=chatgpt.com Clicked the second card in the Sources panel; it pointed at the inline-citation test URL (both cards share a title). No Referer. Data
Search result or link cards: Missing · 2026-10-20 · Verified (manual) · ChatGPT 26.1013.40934 (macOS app) → Chrome 155 / macOS 27.2. Referer: (none) document.referrer: (none) Landing URL: https://attribution.now/t/ref-01/openai-chatgpt/macos/search-cards?utm_source=chatgpt.com Clicked the title of the bordered result card under "Exact match" after a web search. The card may be answer formatting rather than a native search card. Data
Deep research / research report: Missing · 2026-10-20 · Verified (manual) · ChatGPT 26.1013.40934 (macOS app) → Chrome 155 / macOS 27.2. Referer: (none) document.referrer: (none) Landing URL: https://attribution.now/t/ref-01/openai-chatgpt/macos/deep-research Clicked the superscript citation inside the deep research report panel. No Referer. Data
Canvas / document / artifact view: Missing · 2026-10-20 · Verified (manual) · ChatGPT 26.1013.40934 (macOS app) → Chrome 155 / macOS 27.2. Referer: (none) document.referrer: (none) Landing URL: https://attribution.now/t/ref-01/openai-chatgpt/macos/canvas Asked for a canvas; ChatGPT replied "Canvas is no longer available" and made an inline "Writing" block instead. Clicked the link in that block. No Referer. Data
Link or URL written in answer text: Missing · 2026-10-20 · Verified (manual) · ChatGPT 26.1013.40934 (macOS app) → Chrome 155 / macOS 27.2. Referer: (none) document.referrer: (none) Landing URL: https://attribution.now/t/ref-01/openai-chatgpt/macos/bare-url?utm_source=chatgpt.com A URL written without https:// stayed plain text; with https:// it became a link. No Referer. Data
Link the user pasted, echoed back: Missing · 2026-10-20 · Verified (manual) · ChatGPT 26.1013.40934 (macOS app) → Chrome 155 / macOS 27.2. Referer: (none) document.referrer: (none) Landing URL: https://attribution.now/t/ref-01/openai-chatgpt/macos/pasted-link?utm_source=chatgpt.com No Referer. Data

Reported: missing (2026-04-21)

All link locations: Missing · 2026-04-21 · Reported. Desktop app passed no referrer (WISLR test, April 12, 2026). Source Data

REF-02 No full-URL leak

n/a (2026-10-20)

Inline citation in an answer: n/a · 2026-10-20 · Verified (manual) · Chrome 155.0.8059.85 / macOS 27.2. No referrer is sent, so nothing can leak. Data
Sources / citations panel, Search result or link cards, Shopping / product cards, Map / place cards, Deep research / research report, Canvas / document / artifact view, Link or URL written in answer text, Link the user pasted, echoed back, Shared conversation page (public share link): Untested.

Untested

Inline citation in an answer, Sources / citations panel, Search result or link cards, Shopping / product cards, Map / place cards, Deep research / research report, Link or URL written in answer text, Link the user pasted, echoed back, Shared conversation page (public share link): Untested.

Untested

Inline citation in an answer, Sources / citations panel, Search result or link cards, Shopping / product cards, Map / place cards, Deep research / research report, Link or URL written in answer text, Link the user pasted, echoed back: Untested.

Untested

Inline citation in an answer, Sources / citations panel, Search result or link cards, Shopping / product cards, Map / place cards, Deep research / research report, Link or URL written in answer text, Link the user pasted, echoed back: Untested.

n/a (2026-10-20)

Inline citation in an answer: n/a · 2026-10-20 · Verified (manual) · ChatGPT 26.1013.40934 (macOS app) → Chrome 155 / macOS 27.2. No referrer is sent, so nothing can leak. Data
Sources / citations panel, Search result or link cards, Deep research / research report, Canvas / document / artifact view, Link or URL written in answer text, Link the user pasted, echoed back: Untested.

Untested

Inline citation in an answer, Sources / citations panel, Search result or link cards, Deep research / research report, Canvas / document / artifact view, Link or URL written in answer text, Link the user pasted, echoed back: Untested.

REF-03 Link markup (web only)

Missing (2026-10-20)

Inline citation in an answer: Missing · 2026-10-20 · Verified (manual) · Chrome 155.0.8059.85 / macOS 27.2. Citation links use rel="noopener noreferrer", which removes the referrer despite the page's origin policy. Data
Sources / citations panel, Search result or link cards, Shopping / product cards, Map / place cards, Deep research / research report, Canvas / document / artifact view, Shared conversation page (public share link): Missing · 2026-10-14 · Reported. window.open with "noopener,noreferrer" (Search Engine Roundtable). Source Data
Link or URL written in answer text: Missing · 2026-10-20 · Verified (manual) · Chrome 155.0.8059.85 / macOS 27.2. Links in answer text and the "Primary sources" list use rel="noopener noreferrer". Data
Link the user pasted, echoed back: Missing · 2026-10-20 · Verified (manual) · Chrome 155.0.8059.85 / macOS 27.2. Echoed links use rel="noopener noreferrer". Data

Untested

Inline citation in an answer, Sources / citations panel, Search result or link cards, Shopping / product cards, Map / place cards, Deep research / research report, Link or URL written in answer text, Link the user pasted, echoed back, Shared conversation page (public share link): Untested.

n/a

UTM-01 UTM present

Works (2026-10-20)

Inline citation in an answer: Works · 2026-10-20 · Verified (manual) · Chrome 155.0.8059.85 / macOS 27.2. Landing URL: https://www.rfc-editor.org/rfc/rfc9110.html?utm_source=chatgpt.com utm_source=chatgpt.com on every citation link. Data
Sources / citations panel, Search result or link cards, Shopping / product cards, Map / place cards, Deep research / research report, Canvas / document / artifact view, Shared conversation page (public share link): Works · 2026-10-16 · Reported. About 99% of answers with cited links had at least one tagged link again by Oct 16, 06:30 UTC (Profound: https://www.tryprofound.com/blog/chatgpt-missing-utm-tags). Source Data
Link or URL written in answer text: Works · 2026-10-20 · Verified (manual) · Chrome 155.0.8059.85 / macOS 27.2. utm_source=chatgpt.com on every link in the answer text. Data
Link the user pasted, echoed back: Works · 2026-10-20 · Verified (manual) · Chrome 155.0.8059.85 / macOS 27.2. utm_source=chatgpt.com added to echoed links. The visible link text stays unchanged; only the href is tagged. Data

Untested

Inline citation in an answer, Sources / citations panel, Search result or link cards, Shopping / product cards, Map / place cards, Deep research / research report, Link or URL written in answer text, Link the user pasted, echoed back, Shared conversation page (public share link): Untested.

Reported: works (2026-04-21)

All link locations: Works · 2026-04-21 · Reported. WISLR: "The app passes utm_source=chatgpt.com on outbound links." Source Data

Reported: works (2026-04-21)

All link locations: Works · 2026-04-21 · Reported. WISLR: "The app passes utm_source=chatgpt.com on outbound links." Source Data

Partial (2026-10-20)

Inline citation in an answer: Works · 2026-10-20 · Verified (manual) · ChatGPT 26.1013.40934 (macOS app) → Chrome 155 / macOS 27.2. Landing URL: https://attribution.now/t/ref-01/openai-chatgpt/macos/inline-citation?utm_source=chatgpt.com utm_source=chatgpt.com. Data
Sources / citations panel: Works · 2026-10-20 · Verified (manual) · ChatGPT 26.1013.40934 (macOS app) → Chrome 155 / macOS 27.2. Landing URL: https://attribution.now/t/ref-01/openai-chatgpt/macos/inline-citation?utm_source=chatgpt.com utm_source=chatgpt.com. Data
Search result or link cards: Works · 2026-10-20 · Verified (manual) · ChatGPT 26.1013.40934 (macOS app) → Chrome 155 / macOS 27.2. Landing URL: https://attribution.now/t/ref-01/openai-chatgpt/macos/search-cards?utm_source=chatgpt.com utm_source=chatgpt.com. Data
Deep research / research report: Missing · 2026-10-20 · Verified (manual) · ChatGPT 26.1013.40934 (macOS app) → Chrome 155 / macOS 27.2. Landing URL: https://attribution.now/t/ref-01/openai-chatgpt/macos/deep-research No utm_source on the deep research report citation, unlike every chat-answer link. Data
Canvas / document / artifact view: Missing · 2026-10-20 · Verified (manual) · ChatGPT 26.1013.40934 (macOS app) → Chrome 155 / macOS 27.2. Landing URL: https://attribution.now/t/ref-01/openai-chatgpt/macos/canvas No utm_source on the link inside the Writing block (canvas replacement); confirmed on the echo page. Data
Link or URL written in answer text: Works · 2026-10-20 · Verified (manual) · ChatGPT 26.1013.40934 (macOS app) → Chrome 155 / macOS 27.2. Landing URL: https://attribution.now/t/ref-01/openai-chatgpt/macos/bare-url?utm_source=chatgpt.com utm_source=chatgpt.com. Data
Link the user pasted, echoed back: Works · 2026-10-20 · Verified (manual) · ChatGPT 26.1013.40934 (macOS app) → Chrome 155 / macOS 27.2. Landing URL: https://attribution.now/t/ref-01/openai-chatgpt/macos/pasted-link?utm_source=chatgpt.com utm_source=chatgpt.com added to echoed links. Data

Reported: works (2026-04-21)

All link locations: Works · 2026-04-21 · Reported. WISLR: the desktop app adds utm_source=chatgpt.com "reliably". Source Data

MRG-01 Keeps existing query

Works (2026-10-20)

Inline citation in an answer, Sources / citations panel, Search result or link cards, Shopping / product cards, Map / place cards, Deep research / research report, Canvas / document / artifact view, Link or URL written in answer text, Shared conversation page (public share link): Untested.
Link the user pasted, echoed back: Works · 2026-10-20 · Verified (manual) · Chrome 155.0.8059.85 / macOS 27.2. ?a=1&b=2 kept in order; tag appended after them. Data

Untested

Inline citation in an answer, Sources / citations panel, Search result or link cards, Shopping / product cards, Map / place cards, Deep research / research report, Link or URL written in answer text, Link the user pasted, echoed back, Shared conversation page (public share link): Untested.

Untested

Inline citation in an answer, Sources / citations panel, Search result or link cards, Shopping / product cards, Map / place cards, Deep research / research report, Link or URL written in answer text, Link the user pasted, echoed back: Untested.

Untested

Inline citation in an answer, Sources / citations panel, Search result or link cards, Shopping / product cards, Map / place cards, Deep research / research report, Link or URL written in answer text, Link the user pasted, echoed back: Untested.

Works (2026-10-20)

Inline citation in an answer, Sources / citations panel, Search result or link cards, Deep research / research report, Canvas / document / artifact view, Link or URL written in answer text: Untested.
Link the user pasted, echoed back: Works · 2026-10-20 · Verified (manual) · ChatGPT 26.1013.40934 (macOS app) → Chrome 155 / macOS 27.2. Landing URL: https://attribution.now/t/mrg-01/openai-chatgpt/macos/pasted-link?a=1&b=2&utm_source=chatgpt.com ?a=1&b=2 kept in order; tag appended after them. Data

Untested

Inline citation in an answer, Sources / citations panel, Search result or link cards, Deep research / research report, Canvas / document / artifact view, Link or URL written in answer text, Link the user pasted, echoed back: Untested.

MRG-02 Keeps fragment

Works (2026-10-20)

Inline citation in an answer, Sources / citations panel, Search result or link cards, Shopping / product cards, Map / place cards, Deep research / research report, Canvas / document / artifact view, Shared conversation page (public share link): Untested.
Link or URL written in answer text: Works · 2026-10-20 · Verified (manual) · Chrome 155.0.8059.85 / macOS 27.2. Landing URL: https://www.rfc-editor.org/rfc/rfc9110.html?utm_source=chatgpt.com#section-10.1.3 Tag inserted before the existing fragment. Data
Link the user pasted, echoed back: Works · 2026-10-20 · Verified (manual) · Chrome 155.0.8059.85 / macOS 27.2. Landing URL: https://main--attribution-now--keepthebyte.aem.page/t/mrg-02/openai-chatgpt/web-desktop/pasted-link?utm_source=chatgpt.com#section-2 Fragment kept; tag inserted before it. Data

Untested

Inline citation in an answer, Sources / citations panel, Search result or link cards, Shopping / product cards, Map / place cards, Deep research / research report, Link or URL written in answer text, Link the user pasted, echoed back, Shared conversation page (public share link): Untested.

Untested

Inline citation in an answer, Sources / citations panel, Search result or link cards, Shopping / product cards, Map / place cards, Deep research / research report, Link or URL written in answer text, Link the user pasted, echoed back: Untested.

Untested

Inline citation in an answer, Sources / citations panel, Search result or link cards, Shopping / product cards, Map / place cards, Deep research / research report, Link or URL written in answer text, Link the user pasted, echoed back: Untested.

Works (2026-10-20)

Inline citation in an answer, Sources / citations panel, Search result or link cards, Deep research / research report, Canvas / document / artifact view, Link or URL written in answer text: Untested.
Link the user pasted, echoed back: Works · 2026-10-20 · Verified (manual) · ChatGPT 26.1013.40934 (macOS app) → Chrome 155 / macOS 27.2. Landing URL: https://attribution.now/t/mrg-02/openai-chatgpt/macos/pasted-link?utm_source=chatgpt.com#section-2 Fragment kept; tag inserted before it. Data

Untested

Inline citation in an answer, Sources / citations panel, Search result or link cards, Deep research / research report, Canvas / document / artifact view, Link or URL written in answer text, Link the user pasted, echoed back: Untested.

MRG-03 No overwrite

Missing (2026-10-20)

Inline citation in an answer, Sources / citations panel, Search result or link cards, Shopping / product cards, Map / place cards, Deep research / research report, Canvas / document / artifact view, Link or URL written in answer text, Shared conversation page (public share link): Untested.
Link the user pasted, echoed back: Missing · 2026-10-20 · Verified (manual) · Chrome 155.0.8059.85 / macOS 27.2. Target with utm_source=newsletter&utm_medium=email arrived with utm_source=chatgpt.com: the site's own value was replaced (utm_medium=email kept). Data

Untested

Inline citation in an answer, Sources / citations panel, Search result or link cards, Shopping / product cards, Map / place cards, Deep research / research report, Link or URL written in answer text, Link the user pasted, echoed back, Shared conversation page (public share link): Untested.

Untested

Inline citation in an answer, Sources / citations panel, Search result or link cards, Shopping / product cards, Map / place cards, Deep research / research report, Link or URL written in answer text, Link the user pasted, echoed back: Untested.

Untested

Inline citation in an answer, Sources / citations panel, Search result or link cards, Shopping / product cards, Map / place cards, Deep research / research report, Link or URL written in answer text, Link the user pasted, echoed back: Untested.

Missing (2026-10-20)

Inline citation in an answer, Sources / citations panel, Search result or link cards, Deep research / research report, Canvas / document / artifact view, Link or URL written in answer text: Untested.
Link the user pasted, echoed back: Missing · 2026-10-20 · Verified (manual) · ChatGPT 26.1013.40934 (macOS app) → Chrome 155 / macOS 27.2. Landing URL: https://attribution.now/t/mrg-03/openai-chatgpt/macos/pasted-link?utm_medium=email&utm_source=chatgpt.com utm_source=newsletter was replaced with utm_source=chatgpt.com (utm_medium=email kept), as on the web. Data

Untested

Inline citation in an answer, Sources / citations panel, Search result or link cards, Deep research / research report, Canvas / document / artifact view, Link or URL written in answer text, Link the user pasted, echoed back: Untested.

MRG-04 Signed URLs untouched

Missing (2026-10-20)

Inline citation in an answer, Sources / citations panel, Search result or link cards, Shopping / product cards, Map / place cards, Deep research / research report, Canvas / document / artifact view, Link or URL written in answer text, Shared conversation page (public share link): Untested.
Link the user pasted, echoed back: Missing · 2026-10-20 · Verified (manual) · Chrome 155.0.8059.85 / macOS 27.2. Target with expires=2099-01-01&signature=abc123 arrived with utm_source=chatgpt.com appended, so it is no longer byte-identical. Data

Untested

Inline citation in an answer, Sources / citations panel, Search result or link cards, Shopping / product cards, Map / place cards, Deep research / research report, Link or URL written in answer text, Link the user pasted, echoed back, Shared conversation page (public share link): Untested.

Untested

Inline citation in an answer, Sources / citations panel, Search result or link cards, Shopping / product cards, Map / place cards, Deep research / research report, Link or URL written in answer text, Link the user pasted, echoed back: Untested.

Untested

Inline citation in an answer, Sources / citations panel, Search result or link cards, Shopping / product cards, Map / place cards, Deep research / research report, Link or URL written in answer text, Link the user pasted, echoed back: Untested.

Missing (2026-10-20)

Inline citation in an answer, Sources / citations panel, Search result or link cards, Deep research / research report, Canvas / document / artifact view, Link or URL written in answer text: Untested.
Link the user pasted, echoed back: Missing · 2026-10-20 · Verified (manual) · ChatGPT 26.1013.40934 (macOS app) → Chrome 155 / macOS 27.2. Landing URL: https://attribution.now/t/mrg-04/openai-chatgpt/macos/pasted-link?expires=2099-01-01&signature=abc123&utm_source=chatgpt.com utm_source=chatgpt.com appended to the signed URL, so it is no longer byte-identical. Data

Untested

Inline citation in an answer, Sources / citations panel, Search result or link cards, Deep research / research report, Canvas / document / artifact view, Link or URL written in answer text, Link the user pasted, echoed back: Untested.

Lab-wide

Test

All surfaces

UTM-02 UTM consistent

Untested

UTM-03 UTM documented

Reported: works (2026-10-19)

All link locations: Works · 2026-10-19 · Reported. Publishers and Developers FAQ: "ChatGPT automatically includes the UTM parameter utm_source=chatgpt.com in referral URLs." (page text confirmed via search index; direct fetch returned 403). Source Data

OPS-01 Changelog

Reported: missing (2026-10-16)

All link locations: Missing · 2026-10-16 · Reported. The October change and fix were found and reported by third parties; no public OpenAI note at time of writing (Relevant Audience). Source Data

Next improvements

Each card has two prompts you can paste: one for a coding assistant working in your codebase, one to file a ticket.

Title

Send the chatgpt.com referrer on every web link location

Surfaces

Web (desktop), Web (mobile)

Tests

REF-01, REF-03

Summary

chatgpt.com already sets an origin referrer policy, but every outbound link also has rel="noopener noreferrer", so no referrer arrives and sites that rely on it count the visit as Direct.

Suggested fix

Drop noreferrer from the outbound link component and keep noopener. The page's existing origin policy then sends https://chatgpt.com/ and nothing more. Add a regression test that checks each link location.

Copy prompt: fix in your coding harness

You are working in the codebase for ChatGPT (Web (desktop), Web (mobile)).

Goal: improve attribution on outbound links so websites can see visits came from ChatGPT.

Current behavior (as of 2026-10-20, manual test):
chatgpt.com already sets an `origin` referrer policy, but every outbound link also has `rel="noopener noreferrer"`, so no referrer arrives and sites that rely on it count the visit as Direct.

Target behavior:
- REF-01: Request to the target carries `Referer` with the assistant's origin (e.g. `https://chatgpt.com/`).
- REF-03: Citation links use `noopener` without `noreferrer`; page/link referrer policy is `origin` or `strict-origin-when-cross-origin`.

Implementation guidance:
- Find where outbound links are rendered or opened for: inline citation in an answer; sources / citations panel; search result or link cards; shopping / product cards; map / place cards; deep research / research report; canvas / document / artifact view; link or URL written in answer text; link the user pasted, echoed back; shared conversation page (public share link).
- Web: remove `noreferrer` from citation links; keep `noopener`; set referrer policy to `origin` or `strict-origin-when-cross-origin`. Avoid `window.open(url, "_blank", "noopener,noreferrer")`.
- Add `utm_source=chatgpt.com` (the documented value) using safe merging: keep existing query and fragment, never overwrite existing utm_* params, skip signed/expiring URLs.
- Native apps: open links so the platform passes what it can (Android Custom Tabs with an app referrer); rely on the UTM where no referrer is possible.
- Add tests using these vectors: https://attribution.now/tests#test-vectors

Verify by opening https://attribution.now/t/check from each changed surface; the page shows the referrer and UTM it received.

Reference: https://attribution.now/best-practices

Copy prompt: file a ticket

Create a ticket in our tracker for the following.

Title: Send the chatgpt.com referrer on every web link location
Component: Web (desktop), Web (mobile) — outbound links
Type: Improvement
Summary: chatgpt.com already sets an `origin` referrer policy, but every outbound link also has `rel="noopener noreferrer"`, so no referrer arrives and sites that rely on it count the visit as Direct.
Current behavior: as of 2026-10-20 (manual test).
Why it matters: Websites receiving visits from ChatGPT count them as "Direct" traffic when no referrer or UTM arrives, which hides the value ChatGPT sends to publishers and brands.
Acceptance criteria:
- [ ] REF-01: Request to the target carries `Referer` with the assistant's origin (e.g. `https://chatgpt.com/`).
- [ ] REF-03: Citation links use `noopener` without `noreferrer`; page/link referrer policy is `origin` or `strict-origin-when-cross-origin`.
Verification: open https://attribution.now/t/check from Web (desktop), Web (mobile) and confirm the referrer/UTM shown.
References: https://attribution.now/labs/openai-chatgpt · https://attribution.now/best-practices

Title

Keep sites' own UTM tags and signed URLs intact

Surfaces

Web (desktop), Web (mobile), iOS app, Android app, macOS app, Windows app

Tests

MRG-03, MRG-04

Summary

ChatGPT already merges the tag cleanly into existing queries and fragments. Two edge cases remain: a link that already has utm_source=newsletter gets it replaced with chatgpt.com, and signed URLs (with signature or expires) get the tag appended, which can break them.

Suggested fix

Skip tagging when the URL already has a utm_* parameter or a signature/expiry parameter, as in the reference implementation and test vectors.

Copy prompt: fix in your coding harness

You are working in the codebase for ChatGPT (Web (desktop), Web (mobile), iOS app, Android app, macOS app, Windows app).

Goal: improve attribution on outbound links so websites can see visits came from ChatGPT.

Current behavior (as of 2026-10-20, manual test):
ChatGPT already merges the tag cleanly into existing queries and fragments. Two edge cases remain: a link that already has `utm_source=newsletter` gets it replaced with `chatgpt.com`, and signed URLs (with `signature` or `expires`) get the tag appended, which can break them.

Target behavior:
- MRG-03: Target with existing `utm_source=newsletter` keeps that value.
- MRG-04: Target with `signature`/`token`/`expires` params arrives byte-identical.

Implementation guidance:
- Find where outbound links are rendered or opened for: inline citation in an answer; sources / citations panel; search result or link cards; shopping / product cards; map / place cards; deep research / research report; canvas / document / artifact view; link or URL written in answer text; link the user pasted, echoed back; shared conversation page (public share link).
- Web: remove `noreferrer` from citation links; keep `noopener`; set referrer policy to `origin` or `strict-origin-when-cross-origin`. Avoid `window.open(url, "_blank", "noopener,noreferrer")`.
- Add `utm_source=chatgpt.com` (the documented value) using safe merging: keep existing query and fragment, never overwrite existing utm_* params, skip signed/expiring URLs.
- Native apps: open links so the platform passes what it can (Android Custom Tabs with an app referrer); rely on the UTM where no referrer is possible.
- Add tests using these vectors: https://attribution.now/tests#test-vectors

Verify by opening https://attribution.now/t/check from each changed surface; the page shows the referrer and UTM it received.

Reference: https://attribution.now/best-practices

Copy prompt: file a ticket

Create a ticket in our tracker for the following.

Title: Keep sites' own UTM tags and signed URLs intact
Component: Web (desktop), Web (mobile), iOS app, Android app, macOS app, Windows app — outbound links
Type: Improvement
Summary: ChatGPT already merges the tag cleanly into existing queries and fragments. Two edge cases remain: a link that already has `utm_source=newsletter` gets it replaced with `chatgpt.com`, and signed URLs (with `signature` or `expires`) get the tag appended, which can break them.
Current behavior: as of 2026-10-20 (manual test).
Why it matters: Websites receiving visits from ChatGPT count them as "Direct" traffic when no referrer or UTM arrives, which hides the value ChatGPT sends to publishers and brands.
Acceptance criteria:
- [ ] MRG-03: Target with existing `utm_source=newsletter` keeps that value.
- [ ] MRG-04: Target with `signature`/`token`/`expires` params arrives byte-identical.
Verification: open https://attribution.now/t/check from Web (desktop), Web (mobile), iOS app, Android app, macOS app, Windows app and confirm the referrer/UTM shown.
References: https://attribution.now/labs/openai-chatgpt · https://attribution.now/best-practices

Title

Pass an app referrer from the Android app

Surfaces

Android app

Tests

REF-01

Summary

The Android app carries the UTM tag, but no referrer arrives, so tools that rely on the referrer see Direct.

Suggested fix

Open links in a Custom Tab and set Intent.EXTRA_REFERRER to android-app://com.openai.chatgpt, so the browser can pass an app referrer.

Copy prompt: fix in your coding harness

You are working in the codebase for ChatGPT (Android app).

Goal: improve attribution on outbound links so websites can see visits came from ChatGPT.

Current behavior (as of 2026-04-21, third-party report, not yet verified by attribution.now):
The Android app carries the UTM tag, but no referrer arrives, so tools that rely on the referrer see Direct.

Target behavior:
- REF-01: Request to the target carries `Referer` with the assistant's origin (e.g. `https://chatgpt.com/`).

Implementation guidance:
- Find where outbound links are rendered or opened for: inline citation in an answer; sources / citations panel; search result or link cards; shopping / product cards; map / place cards; deep research / research report; link or URL written in answer text; link the user pasted, echoed back.
- Web: remove `noreferrer` from citation links; keep `noopener`; set referrer policy to `origin` or `strict-origin-when-cross-origin`. Avoid `window.open(url, "_blank", "noopener,noreferrer")`.
- Add `utm_source=chatgpt.com` (the documented value) using safe merging: keep existing query and fragment, never overwrite existing utm_* params, skip signed/expiring URLs.
- Native apps: open links so the platform passes what it can (Android Custom Tabs with an app referrer); rely on the UTM where no referrer is possible.
- Add tests using these vectors: https://attribution.now/tests#test-vectors

Verify by opening https://attribution.now/t/check from each changed surface; the page shows the referrer and UTM it received.

Reference: https://attribution.now/best-practices

Copy prompt: file a ticket

Create a ticket in our tracker for the following.

Title: Pass an app referrer from the Android app
Component: Android app — outbound links
Type: Improvement
Summary: The Android app carries the UTM tag, but no referrer arrives, so tools that rely on the referrer see Direct.
Current behavior: as of 2026-04-21 (third-party report, not yet verified by attribution.now).
Why it matters: Websites receiving visits from ChatGPT count them as "Direct" traffic when no referrer or UTM arrives, which hides the value ChatGPT sends to publishers and brands.
Acceptance criteria:
- [ ] REF-01: Request to the target carries `Referer` with the assistant's origin (e.g. `https://chatgpt.com/`).
Verification: open https://attribution.now/t/check from Android app and confirm the referrer/UTM shown.
References: https://attribution.now/labs/openai-chatgpt · https://attribution.now/best-practices

Title

Publish a changelog for link behavior

Surfaces

Web (desktop), Web (mobile), iOS app, Android app, macOS app, Windows app

Tests

OPS-01

Summary

The October 2026 change was found by analytics vendors, not announced, so sites spent a week guessing why ChatGPT traffic dropped.

Suggested fix

Add a dated "Link attribution" section to the publisher FAQ or release notes, and note there whenever the referrer or UTM behavior changes.

Copy prompt: fix in your coding harness

You are working in the codebase for ChatGPT (Web (desktop), Web (mobile), iOS app, Android app, macOS app, Windows app).

Goal: improve attribution on outbound links so websites can see visits came from ChatGPT.

Current behavior (as of 2026-10-16, third-party report, not yet verified by attribution.now):
The October 2026 change was found by analytics vendors, not announced, so sites spent a week guessing why ChatGPT traffic dropped.

Target behavior:
- OPS-01: Lab publishes link-behavior changes (help page, release notes).

Implementation guidance:
- Find where outbound links are rendered or opened for: inline citation in an answer; sources / citations panel; search result or link cards; shopping / product cards; map / place cards; deep research / research report; canvas / document / artifact view; link or URL written in answer text; link the user pasted, echoed back; shared conversation page (public share link).
- Web: remove `noreferrer` from citation links; keep `noopener`; set referrer policy to `origin` or `strict-origin-when-cross-origin`. Avoid `window.open(url, "_blank", "noopener,noreferrer")`.
- Add `utm_source=chatgpt.com` (the documented value) using safe merging: keep existing query and fragment, never overwrite existing utm_* params, skip signed/expiring URLs.
- Native apps: open links so the platform passes what it can (Android Custom Tabs with an app referrer); rely on the UTM where no referrer is possible.
- Add tests using these vectors: https://attribution.now/tests#test-vectors

Verify by opening https://attribution.now/t/check from each changed surface; the page shows the referrer and UTM it received.

Reference: https://attribution.now/best-practices

Copy prompt: file a ticket

Create a ticket in our tracker for the following.

Title: Publish a changelog for link behavior
Component: Web (desktop), Web (mobile), iOS app, Android app, macOS app, Windows app — outbound links
Type: Improvement
Summary: The October 2026 change was found by analytics vendors, not announced, so sites spent a week guessing why ChatGPT traffic dropped.
Current behavior: as of 2026-10-16 (third-party report, not yet verified by attribution.now).
Why it matters: Websites receiving visits from ChatGPT count them as "Direct" traffic when no referrer or UTM arrives, which hides the value ChatGPT sends to publishers and brands.
Acceptance criteria:
- [ ] OPS-01: Lab publishes link-behavior changes (help page, release notes).
Verification: open https://attribution.now/t/check from Web (desktop), Web (mobile), iOS app, Android app, macOS app, Windows app and confirm the referrer/UTM shown.
References: https://attribution.now/labs/openai-chatgpt · https://attribution.now/best-practices

Shipped

2026-10-15: ChatGPT restored the utm_source=chatgpt.com tag. Thank you to the OpenAI team for confirming within hours and shipping the fix within a day.

Full history on the changelog.

Last verified: 2026-10-20. Last checked: 2026-10-20.

Work on ChatGPT and see something out of date? Request a review and we will update the entry.

title

ChatGPT link attribution status

description

Referrer and UTM status for ChatGPT links, by surface and link location, with next improvements.