Attestum
Sealed. Verified. Yours.
Tamper-proof references, verified documents, and sealed credentials. Created in minutes, owned forever.
Professional reference
Written by Sarah Chen · Senior Engineering Manager
Sealed with Attestum™
- End-to-end encrypted
- Tamper-proof
- Independently verifiable
- Owned by you forever
SEE IT WORK
Don't take our word for it. Try it yourself.
Drop any two files. Change a single character in one. The seal breaks. Your files never leave your browser.
CONTENT VERIFICATION
See How It Works
Every file has a unique digital fingerprint. Change even one character, and the fingerprint changes completely.
Drop your original file
or click to browse · any file · max 100 MB
Drop a file to compare
Ready to seal a document permanently?
Seal a DocumentPrivacy by design. Every file is hashed locally in your browser. Attestum never sees your file. We never receive it.
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Seal a document →THE PROBLEM
Anyone can generate a perfect reference.
Nobody can tell if it's real.
AI has made professional documents trivially easy to create and impossibly hard to verify. Reference letters, credentials, and endorsements that look flawless, but were written by no one.
Before Attestum
- Reference calls take 15–20 minutes each, and scheduling adds days
- Recommendations and endorsements with no way to verify who actually wrote them
- Credentials sit in silos you don't control
- No way to prove who actually wrote something
With Attestum
- Verify a sealed reference in 10 seconds: identity confirmed, content untouched
- Know who wrote it: verified identity, professional history, corroborated across independent sources
- You own your records: share them, download them, take them anywhere
- Sealed records can't be edited or faked, by anyone, not even us
WHO IT'S FOR
Built around professionals. Useful for everyone they work with.
FOR PROFESSIONALS
Your references should belong to you.
Collect sealed, verified references once. Share them with any recruiter, for any role, forever. Your professional reputation, finally portable.
Free to create. Free to share. Yours forever.
FOR RECRUITERS
Verify references in 10 seconds, not 10 phone calls.
Sealed references you can trust, instantly. No scheduling, no phone tag, no fakes.
FOR REFEREES & ENDORSERS
Write it once. Make it count forever.
Your reputation is valuable. A sealed reference you write stands permanently. No more repeated calls for the same person.
FOR CREATORS & RESEARCHERS
Prove you made it, before anyone can claim they did.
Seal your work, build a body of proof, share it on your terms. Proof of authorship in a world where anything can be generated.
VERIFIED IDENTITY
Know who's behind every reference
A sealed reference is only as trustworthy as the person who wrote it. Attestum verifies identity through multiple independent signals. The more signals that align, the harder it is to fake.
Work email confirmed
The author verified access to a legitimate work email; not a personal account, not a throwaway.
Professional identity corroborated
Their professional presence is independently discoverable, matching profiles across platforms they don't control.
History that can't be manufactured
Archived records going back months or years. A fake identity has no trail, a real one does.
Endorsed by trusted professionals
Senior professionals vouch for newcomers. The weight of an endorsement depends on the reputation of the person giving it.
Each signal is independently verifiable. Together, they make faking an identity more expensive than being real. Trust compounds over time.
HOW IT WORKS
Four steps from create to verified
The same engine powers every attestation type: references, credentials, document proofs, and more.
Create
Write a reference, upload a document, or submit a credential. Your content is encrypted in your browser before it ever touches our servers.
Seal
A tamper-proof fingerprint of your content is sealed permanently. If anyone changes even one character, the proof breaks.
Own
You control your record. Share it, revoke it, keep it forever. Your professional reputation belongs to you, not to any platform.
Verify
Anyone with a link can verify authenticity in seconds. No phone calls. No intermediaries. No waiting.
Explore what you can verify
Professional Attestations
Sealed references and client reviews from verified professionals. Credentials coming soon.
- ReferencesLive
- ReviewsLive
- CredentialsComing soon
Content Verification
Prove any file existed as-is at a specific moment. Bind your verified identity to prove authorship.
- Seal a documentLive
- Identity-bound sealsLive
- Verify a documentLive
- Project snapshotsComing soon
TRUST & SECURITY
Why trust Attestum?
We built the system to work even when you don't trust us. That's the point.
End-to-end encrypted
Your content is encrypted in your browser before it reaches our servers. Even Attestum can't read it.
Tamper-proof, permanently
Every record includes a cryptographic fingerprint sealed permanently. If anyone changes even one character, the proof breaks.
Owned by you
Download your records at any time. Even if Attestum disappeared, your cryptographic proof remains independently verifiable.
Own your professional reputation, starting today
Request your first sealed reference or seal a document in under a minute — free.
Free during early access · All features included · No credit card needed
Seal · Share · Verify