No integration, no software to install, and the file never leaves your computer
Seal a file today. Prove later that nobody changed it.
An advice note, a signed contract, an email you sent, a report you filed: choose the file below and press Seal. Your browser computes its fingerprint; we record only a salted fingerprint of that, in a log nobody can edit, including us. You download a small receipt and keep it next to the file. Years later, anyone you give both to can check, on this page or with the free offline verifiers, that the file is exactly the one sealed, and when.
Seal
Get a free sandbox key here
No form, no email, no account. Sandbox keys seal up to 50 files a day.
Keep the receipt with the file. It holds the salt that links them; without it nobody, including us, can show which file was sealed.
Check
Given a file and its receipt, this checks that the file is the one sealed, that the log recorded it, and that we signed the log’s state, against our published key. Nothing is uploaded.
What a seal proves, and what it does not
- It proves
- that this exact file existed no later than the moment its seal entered the log, and has not changed by a single byte since. The log’s signed state is time-stamped by two independent authorities (not qualified under eIDAS) and anchored in Bitcoin.
- It does not prove
- who wrote the file, that what it says is true, or that it satisfies any law. It shows the file is the one you had at the time; whether that file is enough is yours to judge.
- Checkable without us
- The receipt is a standard record bundle. The open-source verifiers check it
offline:
python3 riskrouter_verify.py receipt.json --key anchors/. Verifiers and keys - For many files
- Sealing by hand suits a few files a day. For every advice note your software writes, the same seal is one API call from inside it. Integrate