Compute SHA-256 and SHA-1 fingerprints of public keys.
Key Fingerprint does its work in front of you rather than sending anything away to be processed. What you see is the whole of it.
Nothing here is stored between visits. Reload the page and you start from an empty box again.
You will find it under Keys & certificates, alongside 7 other tools for the same sort of job.
Accepts PEM and JWK key formats with colon-separated and hex output.
-----BEGIN PUBLIC KEY----- MIIBIjANBgkqhkiG9w0BAQEFAAOCAQ8AMIIBCgKCAQEAzbcx4tfj8K+lXzGe7ihp UO8AZSKtTIWOQIEeCYQjnoxv0GGBr9GU9viLZXvUdDi4weZkoyXBJGbdLsW2Otpo tcsMUk2MRzxE61BB3QUJBlIK8h4SjmHGrrwQFbo48fKnDr7I/sk17TRmil94d6hA sGhyyoJOqlQp4gJ5tRZpdwwzYNvMOm7jjYkTyTQ2q+Jyw1DDemwi0GRrtuB3ciD0 Ogl/B8lU8uekK8vq2iDiLXH6JWL997lLNJJBr/oH7NbhbpNDR2DZ7VA4lUyPNDBs Xn99uVFw0ueo7SrlOe1Zuz7XQy1xdorISLfp4ZFUk5Iaf0JykysJLUA4u0lJ+SUF VwIDAQAB -----END PUBLIC KEY-----
=== Key Fingerprints === Key size: 294 bytes SHA-256: 21:E5:6D:58:9F:F2:B0:FE:9C:ED:D3:BF:04:AE:F2:F8:DD:9E:DD:9D:89:22:A4:62:4A:17:E3:85:1E:4C:74:4E SHA-256 (hex): 21e56d589ff2b0fe9cedd3bf04aef2f8dd9edd9d8922a4624a17e3851e4c744e SHA-1: A3:7F:10:4F:CC:3B:D8:57:FD:7C:2A:3F:EF:60:5F:D0:7C:1B:D2:1D SHA-1 (hex): a37f104fcc3bd857fd7c2a3fef605fd07c1bd21d
Yes. It is JavaScript running in this tab, so once the page has loaded it needs nothing further from the network. Put the machine in flight mode and it carries on. Nothing you do here is sent anywhere, because there is nowhere for it to go.
No. Reload the page and it starts from nothing. There is no account, no saved state and no cookie holding your last session. That is a deliberate trade: it cannot lose your data because it never keeps any.
Timing comes from performance.now(), the high resolution clock the browser provides, rather than from setInterval, which drifts by a few milliseconds every tick and compounds over minutes. What can still shift things is the browser throttling a tab in the background, so leave it visible if the timing matters.
Where a sound makes sense, it is generated with the Web Audio API rather than loaded as a file, so there is nothing to download and nothing to block. Browsers refuse to start audio until you have interacted with the page, which is why the first press is what switches it on.
Yes. The controls are sized for touch and the layout collapses to one column on a narrow screen. Bear in mind that a phone locking its screen will suspend the page, and timing stops with it.