Check it without taking our word for it

Drop the certificate here and your browser computes its fingerprint. The file is not uploaded, it never touches our servers and nothing is recorded anywhere.

Drop the certificate here

or

PDF only, up to 25 MB

Three steps, and none of them rests on our word

  1. The fingerprint is computed

    A fingerprint is a fixed-length summary of the whole document. Two files that differ by a single byte produce fingerprints with nothing in common. It is computed here, in your browser.

  2. It is compared with what was anchored

    When the certificate was sealed, that same fingerprint was written to a public chain. It is timestamped and it cannot be rewritten.

  3. It matches or it does not

    There is no middle ground, no interpretation and no judgement of ours. Either it is the same document or it is not.

Why the file never leaves your browser

A signature certificate carries a person's name. Uploading it to a server to check it would mean asking them to trust again, on the very page that exists so they do not have to. So the computation happens here, and that is that.

What this does not tell you

  • It does not say whether what the cause asks for is true or reasonable. That is on whoever created it.
  • It does not reveal who signed. The fingerprint contains nobody's data.
  • It stores nothing. Close this tab and no trace of the file or the fingerprint remains.
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