OpenAI
OpenAI API
What OpenAI says OpenAI API puts into the files it makes, by file type, quoted from OpenAI's own pages. Covers GPT Image, audio and text models used through the OpenAI API.
At a glance
| File type | Content Credentials | Invisible watermark | AI label in metadata | Visible mark | Tool named in metadata |
|---|---|---|---|---|---|
| Images | Yes, with exceptions | SynthID, exceptions | Not stated | Not stated | Issuer, model |
| Audio | Not stated | SynthID | Not stated | Not stated | Not stated |
| Text | Not stated | Opt-in | Not stated | Not stated | Not stated |
Images
- Content CredentialsA signed record (C2PA) of how the file was made, sealed so any change shows.
OpenAI says images generated with the OpenAI API include Content Credentials (C2PA) and a SynthID watermark, except from models planned for imminent deprecation, including gpt-image-1 and gpt-image-1.5. Its documented example check response names the issuer as "OpenAI OpCo, LLC".
OpenAI's deprecations page lists API shutdown dates of October 23, 2026 for gpt-image-1 and December 1, 2026 for gpt-image-1.5.
Provenance signals in OpenAI-generated content
Quoted passage Which provenance signals does OpenAI use? (table row: Images; note beneath the table)
Images Content Credentials and SynthID watermarks Images generated with ChatGPT, Codex, or the OpenAI API include both signals. […] Coverage may vary by product, model, export path, file type, and when the content was created. API outputs are covered except for models planned for imminent deprecation, including gpt-image-1, gpt-image-1.5, and sora-2.
Provenance signals in OpenAI-generated content
Quoted passage Which provenance signals does OpenAI use? (table note)
Coverage may vary by product, model, export path, file type, and when the content was created. API outputs are covered except for models planned for imminent deprecation, including gpt-image-1, gpt-image-1.5, and sora-2.
Content provenance (OpenAI API guide)
Quoted passage Verify a file (example image response)
"type": "c2pa", "outcome": "detected", "validation_state": "trusted", "issuer": "OpenAI OpCo, LLC", "model": "gpt-image", "generated_at": "2026-07-27T18:34:12Z"
Content provenance (OpenAI API guide)
Quoted passage Content provenance (intro); What content provenance checks
Use the Content Provenance API to check whether an image or audio file contains supported OpenAI provenance signals. […] | C2PA Content Credentials | Images | Signed metadata with issuer and AI-use details | | SynthID | Images and audio | A watermark embedded directly in supported media | C2PA metadata provides more context about a file's origin. Editing, converting, or sharing a file can remove its metadata. A SynthID watermark is part of the image or audio itself and may survive some transformations.
Quoted passage 2026-06-02: GPT Image model deprecations (table); gpt-image-1 table row
| Dec 1, 2026 | `gpt-image-1.5` | `gpt-image-2.5-sunburst` or `gpt-image-2.5-flare` | […] | October 23, 2026 | `gpt-image-1` | `gpt-image-2.5-sunburst` or `gpt-image-2.5-flare` |
- Invisible watermarkA signal woven into the pixels, frames, audio or wording, meant to survive copying.
OpenAI says images generated with the OpenAI API include a SynthID watermark, with the same exception for models planned for imminent deprecation, including gpt-image-1 and gpt-image-1.5.
Provenance signals in OpenAI-generated content
Quoted passage Which provenance signals does OpenAI use? (table row: Images; note beneath the table)
Images Content Credentials and SynthID watermarks Images generated with ChatGPT, Codex, or the OpenAI API include both signals. […] Coverage may vary by product, model, export path, file type, and when the content was created. API outputs are covered except for models planned for imminent deprecation, including gpt-image-1, gpt-image-1.5, and sora-2.
Provenance signals in OpenAI-generated content
Quoted passage Which provenance signals does OpenAI use? (table note)
Coverage may vary by product, model, export path, file type, and when the content was created. API outputs are covered except for models planned for imminent deprecation, including gpt-image-1, gpt-image-1.5, and sora-2.
- AI label in metadataA plain metadata field (IPTC Digital Source Type) saying AI made the content. Anyone can add or remove it.
Not stated. None of OpenAI's pages listed under Sources read says so.
- Visible markA mark you can see, such as a logo or a sparkle in a corner.
Not stated. None of OpenAI's pages listed under Sources read says so.
- Tool named in metadataThe tool or model written into ordinary file fields, such as Software or Creator.
OpenAI's API documentation shows an example check result for an image that names the issuer "OpenAI OpCo, LLC" and the model "gpt-image".
This is an example response, not a full list of fields.
Content provenance (OpenAI API guide)
Quoted passage Content provenance (intro); What content provenance checks
Use the Content Provenance API to check whether an image or audio file contains supported OpenAI provenance signals. […] | C2PA Content Credentials | Images | Signed metadata with issuer and AI-use details | | SynthID | Images and audio | A watermark embedded directly in supported media | C2PA metadata provides more context about a file's origin. Editing, converting, or sharing a file can remove its metadata. A SynthID watermark is part of the image or audio itself and may survive some transformations.
Content provenance (OpenAI API guide)
Quoted passage Verify a file (example image response)
"type": "c2pa", "outcome": "detected", "validation_state": "trusted", "issuer": "OpenAI OpCo, LLC", "model": "gpt-image", "generated_at": "2026-07-27T18:34:12Z"
Audio
- Content CredentialsA signed record (C2PA) of how the file was made, sealed so any change shows.
Not stated. None of OpenAI's pages listed under Sources read says so.
OpenAI's text-to-speech guide gives no provenance statement, and its provenance article lists only SynthID for audio.
- Invisible watermarkA signal woven into the pixels, frames, audio or wording, meant to survive copying.
OpenAI says audio generated by the OpenAI API includes an inaudible SynthID watermark embedded in the audio itself. Its update of July 31, 2026 says supported audio from its tools now includes SynthID.
Provenance signals in OpenAI-generated content
Quoted passage Which provenance signals does OpenAI use? (table row: Audio)
Audio SynthID watermarks Audio generated by ChatGPT or the OpenAI API includes an inaudible watermark embedded in the audio itself.
Advancing content provenance for a safer, more transparent AI ecosystem
Quoted passage Update July 31, 2026 (page header)
Update July 31, 2026: We’re expanding this work beyond images. Supported audio generated with OpenAI tools, including through ChatGPT and the OpenAI API, now includes SynthID watermarking. Our public verification tool will now allow for verification of supported audio files in addition to images.
- AI label in metadataA plain metadata field (IPTC Digital Source Type) saying AI made the content. Anyone can add or remove it.
Not stated. None of OpenAI's pages listed under Sources read says so.
- Visible markA mark you can see, such as a logo or a sparkle in a corner.
Not stated. None of OpenAI's pages listed under Sources read says so.
- Tool named in metadataThe tool or model written into ordinary file fields, such as Software or Creator.
Not stated. None of OpenAI's pages listed under Sources read says so.
Text
- Content CredentialsA signed record (C2PA) of how the file was made, sealed so any change shows.
Not stated. None of OpenAI's pages listed under Sources read says so.
- Invisible watermarkA signal woven into the pixels, frames, audio or wording, meant to survive copying.
OpenAI says API customers anywhere can turn on text watermarking for a project or organization and choose which models receive it; it is off by default. OpenAI then adds the textGrain watermark during generation.
Provenance signals in OpenAI-generated content
Quoted passage Which provenance signals does OpenAI use? (table row: Text)
Text textGrain watermarks (EU only) In the EU, ChatGPT-generated text includes an invisible change to the randomness used in the model’s word choices to comply with the EU AI Act. API customers globally can turn on text watermarks to text outputs, from their project or organization settings.
Provenance signals in OpenAI-generated content
Quoted passage I'm an API customer, how do I turn on text watermarks?
Customers of the OpenAI API can activate text watermarking for a specific project via Settings , or broadly for their entire org via Organization settings . Customers can, in each case, select which model(s) receive a text watermark. Once enabled for a supported model, OpenAI adds the watermark during text generation. Customers do not need to add a separate marking to each response.
Our approach to EU text provenance rules
Quoted passage Introduction (phased approach list)
Starting today, API customers globally will be able to opt in to text watermarking for select models. Text watermarking will remain off by default in the API. Over the coming weeks, we will add an invisible watermark to eligible ChatGPT and Codex text output in the European Union.
- AI label in metadataA plain metadata field (IPTC Digital Source Type) saying AI made the content. Anyone can add or remove it.
Not stated. None of OpenAI's pages listed under Sources read says so.
- Visible markA mark you can see, such as a logo or a sparkle in a corner.
Not stated. None of OpenAI's pages listed under Sources read says so.
- Tool named in metadataThe tool or model written into ordinary file fields, such as Software or Creator.
Not stated. None of OpenAI's pages listed under Sources read says so.
Limits and detection
- Checking tool from the makerA way the maker offers to check a file for its traces.
OpenAI's Content Provenance API checks images for C2PA Content Credentials and images and audio for SynthID, the same checks as openai.com/verify. Text detection is available by application to qualifying organizations, reviewed case by case.
OpenAI's API documentation says editing, converting or sharing a file can remove its metadata.
Content provenance (OpenAI API guide)
Quoted passage Content provenance (intro); What content provenance checks
Use the Content Provenance API to check whether an image or audio file contains supported OpenAI provenance signals. […] | C2PA Content Credentials | Images | Signed metadata with issuer and AI-use details | | SynthID | Images and audio | A watermark embedded directly in supported media | C2PA metadata provides more context about a file's origin. Editing, converting, or sharing a file can remove its metadata. A SynthID watermark is part of the image or audio itself and may survive some transformations.
Provenance signals in OpenAI-generated content
Quoted passage OpenAI's verification tools: How can I check whether content was generated with OpenAI tools?
You can visit openai.com/verify to check whether a supported image or audio file, contains provenance signals associated with content generated or exported by OpenAI tools. After you upload a supported file, the tool will look for supported OpenAI provenance signals, such as a SynthID watermark or a trusted C2PA manifest associated with OpenAI. If the tool finds a supported OpenAI provenance signal, it indicates that the content was likely generated by an OpenAI model. Developers and organizations can also use OpenAI’s Content Provenance API to check images and audio for OpenAI provenance signals and integrate verification into their own applications or workflows.
Provenance signals in OpenAI-generated content
Quoted passage OpenAI's verification tools (text detector access); Who qualifies for text detector access
For text, consistent with our obligations under the EU AI Act, organizations with a qualifying use case, such as academic and research organizations studying text provenance, detection reliability, or how people understand provenance results, are able to apply for text detector access. We will review applications from qualified organizations on a case by case basis […] Academic integrity applications, such as checking student work for AI use (e.g. in writing essays or theses), are also currently outside the program scope.
- What the maker says about limitsIn the maker's own words.
OpenAI says coverage may vary by product, model, export path, file type and creation date, and that API outputs from models planned for imminent deprecation, including gpt-image-1, gpt-image-1.5 and sora-2, are not covered.
Provenance signals in OpenAI-generated content
Quoted passage Which provenance signals does OpenAI use? (table note)
Coverage may vary by product, model, export path, file type, and when the content was created. API outputs are covered except for models planned for imminent deprecation, including gpt-image-1, gpt-image-1.5, and sora-2.
- What the maker says about limitsIn the maker's own words.
OpenAI says it is working with its cloud and distribution providers to embed provenance signals, including watermarks, in eligible image, audio and text outputs, and that availability may vary by output and partner.
Provenance signals in OpenAI-generated content
Quoted passage I access OpenAI's models through a Cloud service. Do those outputs also contain provenance signals?
We are working with all our Cloud and distribution providers to ensure provenance signals including watermarks are embedded in all eligible outputs including image, audio and text. Availability may vary by output and by partner.
- What the maker says about limitsIn the maker's own words.
OpenAI says the Content Provenance API is not a general-purpose AI detector, and that visible watermarks and labels are separate from the signals it checks.
Content provenance (OpenAI API guide)
Quoted passage What content provenance checks (closing paragraph)
The API checks for supported OpenAI signals. It isn't a general-purpose AI detector and doesn't identify content generated by every AI system. Visible watermarks and labels are separate from the provenance signals checked by the API.
Sources read
Each page below was read and the quoted passage found on it. Last verified October 19, 2026.
- Provenance signals in OpenAI-generated contentOpenAI (OpenAI Help Center)
- Verify OpenAI-generated contentOpenAI
- Content provenance (OpenAI API guide)OpenAI (OpenAI API docs)
- Advancing content provenance for a safer, more transparent AI ecosystemOpenAI
- Understanding the source of what we see and hear onlineOpenAI
- Our approach to EU text provenance rulesOpenAI
- Launching Sora responsiblyOpenAI
- Sora 2 System Card: Provenance and Transparency InitiativesOpenAI (Deployment Safety Hub)
- What to know about the Sora discontinuationOpenAI (OpenAI Help Center)
- Introducing 4o Image GenerationOpenAI
- Deprecations (OpenAI API)OpenAI (OpenAI API docs)
- Creating and editing documents, spreadsheets, and presentations with ChatGPT WorkOpenAI (OpenAI Help Center)
- Images in ChatGPTOpenAI (OpenAI Help Center)
- Image generation (OpenAI API guide)OpenAI (OpenAI API docs)
- Text to speech (OpenAI API guide)OpenAI (OpenAI API docs)
- Video generation with Sora (OpenAI API guide)OpenAI (OpenAI API docs)