GreenCheckmark

We resonate much more with authentic photos, compared to AI-generated ones.

It's our human nature.

GreenCheckmark is a special camera app that produces digitally signed photos and videos. Just like signed PDF documents, everyone can verify that your footage was recorded directly from a real camera and has not been altered by human or AI.
Powered by C2PA digital signature standards. C2PA conformant
This signature is valuable because viewers can independently validate what they see is exactly what was captured by the camera.

Camera: verifiable, direct-from-camera, unmodified since capture

Settings: optional creator attribution and location tagging

Signed photo with C2PA banner and link to original

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For the Record

Open, industry-standard C2PA is used to create verifiable videos and photos. You can inspect a media file's digital signature using verify.contentauthenticity.org, Adobe's Content Authenticity Inspect, or the GreenCheckmark Chrome Extension. Native verification in Google Chrome is coming soon too. On iOS and Android you can also share a photo or video into GreenCheckmark to view the embedded C2PA signature.

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Tamper-Evident by Design

Any later change to a signed file — a crop, a filter, a re-encode — breaks the signature, so tampering is detectable quickly.

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C2PA Conformant

GreenCheckmark for iOS and Android is listed on the official C2PA Conforming Products List.

See a GreenCheckmark signature

These photo and video samples were captured and signed with GreenCheckmark. Open the samples page to see each file next to its C2PA signature, or check the same files in verify.contentauthenticity.org or c2paviewer.com.

GreenCheckmark signed sample photo with visual overlay banner

Signed photo

JPEG with an embedded C2PA manifest and GreenCheckmark overlay.

View C2PA signature Download photo

Signed video

MP4 with an embedded C2PA manifest and GreenCheckmark overlay.

View C2PA signature Download video

Additional Features

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Creator Attribution

You can add author information using Sign In with Apple or Sign In with Google. Email only or Email with Name will then be included in digital signatures and visual overlays, establishing creator provenance.

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Location Stamping

You can optionally add location information to digital signatures and GreenCheckmark banners.

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Originals Saved On Cloud

You can optionally save the signed original files. The original URL is visible in the GreenCheckmark banner and is also saved in the C2PA manifest. This allows viewers to access the original footage as recorded in real life.

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Inspect Shared Media

Share a photo or video from Photos, Files, Messages, or another app into GreenCheckmark. The app reads any embedded C2PA signature and shows whether it is trusted, valid, missing, or broken.

Launch offer

Get Pro for free — first 1000 early adopters

For the first 1000 early adopters, you can get GreenCheckmark Pro for free by helping us spread the word. Share a signed GreenCheckmark photo or video with #GreenCheckmarkPro, then upload a screenshot in the app.

What a GreenCheckmark C2PA signature proves

Provenance becomes useful when everyone agrees on what it covers. Here is exactly what our signature does and does not tell you.

It proves

The file came from a camera on a real device running the official GreenCheckmark app, attested by iOS and Android.
Not one byte has changed since capture. Any crop, filter, or re-encode breaks the signature.
Where it happened and who captured it, when the creator chooses to include location or attribution.

It cannot prove

That the photographer was honest about what they pointed the camera at. A camera aimed at a screen or a print still produces a real-life capture of that screen.
Anything about a copy that has been edited, re-encoded, or stripped of its credentials — those simply stop verifying.

Which edition is for me?

Who is Free Edition for?

Anyone who wants to capture and share C2PA-signed photos and videos at no cost. Free includes full cryptographic signing, HSM-backed keys with OS attestation, the GreenCheckmark banner, optional location and creator attribution, and public verification — with no ads and no data selling.

Who is Pro Edition for?

Creators and journalists who want more control over how the GreenCheckmark appears: custom banner placement, a minimal icon-only badge, and optional organization branding (logo and URL). Pro is available via the launch offer for the first 1000 early adopters, or by subscribing in the app.

Who is Enterprise Support for?

Newsrooms and media organizations that need commercial terms, SLA-backed support, dedicated cloud storage, and help rolling GreenCheckmark out across their teams and business partners. Contact us to discuss.

Frequently Asked Questions

Is GreenCheckmark really free? Will my data be monetized?

GreenCheckmark is a non-profit giveback project. The basic version is free and will remain free. We do not sell data and will continue to operate as a not-for-profit organization. Pro subscription and enterprise support fees will be used to cover the ongoing infrastructure and development costs of the platform.

I have just recorded a video using GreenCheckmark. How can I verify it has been properly signed?

In the app, open the capture from the gallery thumbnail and tap Signature to view the C2PA manifest and validation result. You can also share the file into GreenCheckmark from another app to open the same signature view.

Online, use the official C2PA validator at verify.contentauthenticity.org, Adobe's Content Authenticity Inspect, or c2paviewer.com. To try this without capturing first, use our sample signed photo and video.

🎉 New! Google is adding C2PA verification directly inside Chrome, Google Search, and Gemini. This is on top of existing C2PA support inside Google Photos.

🎉 Meta will start labeling C2PA-signed media too. TikTok has recently joined the C2PA organization as well.

Can I check a photo or video that was not taken with GreenCheckmark?

Yes. On iOS and Android, share an image or video from another app into GreenCheckmark (or open it with GreenCheckmark). The app assesses any embedded C2PA signature and shows the validation result. This path only inspects the file — it does not capture, re-sign, or replace the original. Media without a C2PA manifest is reported as unsigned.

What exactly does a GreenCheckmark signature prove?

After the camera captures the media, a C2PA manifest is built on the device and signed. The manifest is stored inside the media file, so it travels with the content and is verifiable by anyone.

What that establishes is provenance and integrity: this footage came from a real camera on an attested device, and nothing has changed since. It is not a judgement about the subject of the photo — see what a GreenCheckmark proves for the full scope.

What is C2PA?

C2PA (Coalition for Content Provenance and Authenticity) is an open technical standard that allows creators to embed information about the origin and history of digital content.

Major companies including Adobe, Microsoft, Google, BBC, Sony, and Nikon form its core. They are also working on implementing it in their products — e.g. Google Pixel 10's camera app, pro cameras such as the Leica M11-P and Nikon Z6III, and many more.

C2PA behaves differently from a watermark. A watermark can be weakened or removed by cropping and re-encoding, and it fails quietly. A cryptographic signature fails loudly: change one byte and verification breaks, so a viewer learns that something happened rather than being left to guess.

Are there more details on how C2PA works on the Pixel camera app?

Yes! Google recently announced Trusted Images for Pixel and Android, which also uses C2PA and hardware security to verify photos.

How can I verify if a GreenCheckmark photo/video has not been modified?

Viewers have several ways to validate it:

Share into the GreenCheckmark app: On iOS or Android, share the photo or video into GreenCheckmark to open the signature view and see whether the C2PA credential is trusted, valid, missing, or invalid.
Online Inspection: Use verify.contentauthenticity.org or Adobe's Content Authenticity Inspect. They verify that the signature is signed by a trusted certificate authority and matches the content. If there are any discrepancies, they will highlight them for you.
Chrome Extension: Install the GreenCheckmark extension to automatically flag images that show a GreenCheckmark banner but have an invalid signature.
Compare with the original asset recorded by the author: Use the original link on the GreenCheckmark banner to download and compare the media you watched against the original. To confirm the two are byte-for-byte identical, generate a SHA-256 hash of each and check that they match.

Is GreenCheckmark a C2PA conformant product?

Yes. Both GreenCheckmark - iOS and GreenCheckmark - Android are listed as conformant generator products on the official C2PA Conforming Products List.

Browse the live listings in the C2PA Conformance Explorer (search for “GreenCheckmark”), or view the published list on GitHub.

We are a Contributor Member of the C2PA organization.

How can I connect with the GreenCheckmark community?

Join the GreenCheckmark community on Reddit at r/GreenCheckmark to:

Share your verified photos and videos
Get help and ask questions
Provide feedback and suggestions
Stay updated on new features and developments
Connect with other users who care about media authenticity

We'd love to have you as part of our growing community!

Stay Updated

Join our mailing list for updates on GreenCheckmark.

Privacy & Data

Data is collected and used only for the purpose of providing user features and improving the service.

We do not sell data to advertisers or data aggregation agencies. Our mission is to serve our communities, not to monetize your content or data.

Open Source Acknowledgements

We are grateful to all the open source contributors who make projects like GreenCheckmark possible.