Timestamp your ideas
on the blockchain.

Your text or file is encrypted in the browser, the proof stored on the Cardano blockchain, and verifiable anytime. Your original never leaves your device.

Create Proof Verify
  • No account
  • Original never uploaded
  • Publicly verifiable

3 ada per proof. No subscription.

Recorded on blockchain Example
Proof fingerprint 41aec2ba3aad…5e2b436eaf9f
Timestamp Sep 20, 2026, 9:18 PM UTC
Network Cardano mainnet
Original never uploaded

How the Commit-Reveal Scheme Works

1

Commit

Enter your text or upload a file. A SHA-256 hash is computed in your browser with a random salt. Only the hash goes on-chain.

2

Store

The hash is written to the Cardano blockchain as transaction metadata: timestamped, permanent, and tamper-proof. Download your proof file (PDF or JSON) with everything needed for later verification.

3

Verify

Share your original text or file and salt. Anyone can recompute the hash, verify it against the on-chain proof, and confirm the exact timestamp.

Learn more about the commit-reveal scheme or read the FAQ

Use cases

Proof of Invention Establish prior art for your inventions: cheaper than a patent, more verifiable than a sealed envelope. Learn more Proof of Creation Show that your designs, photos, code or writing already existed at a given time. Learn more Startup Ideas Timestamp your pitch deck and ideas before sharing them with investors. Learn more Research Priority Show that your findings existed before peer review and before the preprint. Learn more

Pricing

With a Cardano wallet 3 ada

Pay straight from your wallet, plus a network fee of about 0.18 ada.

With card, Apple Pay or Google Pay Priced in euros

No wallet needed. You see the total before paying, and we submit the proof to the blockchain for you.

Common questions

Is my text or file stored on the blockchain?

No. Only a SHA-256 hash of your content goes on-chain. Your original text or file never leaves your browser.

How can I verify you don't capture my ideas?

Open your browser's developer tools (F12 → Network tab) and submit a proof. You'll see that no request ever contains your original text or file, only the hash leaves the page. The hashing runs entirely via the Web Crypto API in your browser. The client-side JavaScript is minified but not obfuscated, so you can inspect the source code in the Sources tab.

What if I lose my proof file?

You can still verify if you have the transaction hash, original text, and salt. The TX hash is visible in your wallet's transaction history or on the Proof Explorer.

Will this hold up in court?

CommitProof is not legal advice, but blockchain timestamps are gaining recognition as evidence worldwide. In 2025, a French court accepted blockchain timestamps as proof of copyright ownership and creation date (AZ Factory v. Valeria Moda). Chinese courts have accepted blockchain evidence since 2018. The EU eIDAS Regulation (Art. 41) states that electronic timestamps cannot be denied legal effect solely because of their form, and Italy recognizes blockchain storage as an electronic timestamp under eIDAS. In the US, states like Vermont treat blockchain records as self-authenticating evidence when accompanied by a sworn declaration. None of this replaces a patent or copyright registration, but a blockchain timestamp can serve as supporting evidence of when something existed. Consult an attorney for advice specific to your jurisdiction and situation.

See all questions

Ready to Timestamp Your Proof?

Create a blockchain-anchored timestamp in under a minute. Your original never leaves your browser.

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3 ada per proof. No subscription.