Encypher Seal
Prove who signed a file and whether it changed.
Seal contracts, reports, filings, and records so anyone can verify who signed them and whether they changed, without an Encypher account.
Seconds
to check a signature and detect post-signing changes
$0
to verify, with no Encypher account required
Office
DOCX, XLSX, and PPTX sign under C2PA 2.4
Seal in action
Sign a photo. Catch the visible edit.
Watch a signed stock photo pass public verification, then see the same verifier flag an added object as modified.
Start sealing freeHow it works
Seal it, send it, anyone verifies
Seal once; verification is public, standards-based, and open to anyone you send the file to.
- 1
Seal it
Drop a file into the dashboard or send it to POST /sign/media. Encypher signs it with a C2PA manifest and an X.509 certificate chain tied to your organization.
- 2
Send it anywhere
The seal lives inside the file itself, not in a lookup service you have to query, so it travels through email, storage, and downloads untouched.
- 3
Anyone checks it
Anyone drags the file onto the public verifier to see whether the signature is valid, the file changed after signing, or the signer is not trusted. No account required.
Try it live
Seal and verify something right now
Live verifier - no account required
Paste your content
Sample article pre-filled. Edit it or paste your own.
Free to try
Paste your text and go. No account, no setup.
Invisible to readers
The mark is hidden inside the text. Anyone reading it sees exactly what you wrote, nothing different.
Anyone can check it
It uses an open standard Encypher helped create, so anyone can confirm where the text came from.
What Seal does
File integrity anyone can check
A C2PA signature rides inside the file, so recipients can inspect the signer and detect post-signing changes without relying on a vendor portal.
Tamper-evident by design
The seal reflects the exact bytes it was applied to. Change a single character and verification reports the document as altered.
Documents and media
Seal supported PDF, image, audio, video, and Microsoft Office formats. DOCX, XLSX, and PPTX sign under C2PA 2.4 and verify version-agnostically; they are not formal C2PA Conformance Program formats.
Check in seconds
Anyone drags a sealed file onto the public verifier to inspect signature validity, signer trust, and post-signing changes, with no account required.
Identity built in
Every paid plan includes a free CAWG identity certificate, pending enrollment and program approval, and white-label identity with a private key from the Encypher root CA is available for teams that want tool identity plus organization identity.
The core guarantee
Verification needs no Encypher account
The seal is a C2PA manifest inside the file. Compatible standards-based tools can check the document signature independently; trust still depends on the signer certificate and its chain.
Independent verification
Any standards-based C2PA verifier that supports the file format can check a seal without Encypher in the loop, so recipients never have to take our word for it.
Audit trail on every operation
Every seal and verification is logged and exportable for compliance reviews.
Where this fits
Legal · Finance · Healthcare · Government · Insurance
For engineers
curl -X POST https://api.encypher.com/api/v1/sign/media \
-H "Authorization: Bearer $ENCYPHER_API_KEY" \
-F "file=@contract.pdf"- C2PA manifests signed with an X.509 certificate chain
- DOCX, XLSX, and PPTX sign under C2PA 2.4 and verify version-agnostically; they are not formal C2PA Conformance Program formats
- White-label identity available: private key issuance from the Encypher root CA
- Audit logs on every operation