Compute SHA-256 and SHA-1 fingerprints of public keys

Create a display fingerprint for a public key or certificate.

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ToolKey Fingerprint
Input
Output
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How it works

The selected key or certificate bytes are canonicalized, hashed with the requested digest, and rendered as hexadecimal or colon-separated octets. Fingerprints identify bytes and do not reveal the private key.

  • SHA-256 is the modern default while older SHA-1 displays remain for compatibility.

Worked example

Compute SHA-256 and SHA-1 fingerprints of public keys
Calculate SHA-256 and SHA-1 fingerprints of a public key
Input
											-----BEGIN PUBLIC KEY-----
MIIBIjANBgkqhkiG9w0BAQEFAAOCAQ8AMIIBCgKCAQEAzbcx4tfj8K+lXzGe7ihp
UO8AZSKtTIWOQIEeCYQjnoxv0GGBr9GU9viLZXvUdDi4weZkoyXBJGbdLsW2Otpo
tcsMUk2MRzxE61BB3QUJBlIK8h4SjmHGrrwQFbo48fKnDr7I/sk17TRmil94d6hA
sGhyyoJOqlQp4gJ5tRZpdwwzYNvMOm7jjYkTyTQ2q+Jyw1DDemwi0GRrtuB3ciD0
Ogl/B8lU8uekK8vq2iDiLXH6JWL997lLNJJBr/oH7NbhbpNDR2DZ7VA4lUyPNDBs
Xn99uVFw0ueo7SrlOe1Zuz7XQy1xdorISLfp4ZFUk5Iaf0JykysJLUA4u0lJ+SUF
VwIDAQAB
-----END PUBLIC KEY-----
Output
												=== 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

When to use this

SSH host verification, certificate pinning, and support investigations compare fingerprints.

Edge cases

  • Hashing PEM text and decoded DER produces different fingerprints.
  • A certificate fingerprint differs from its public-key digest label.
  • Changing case or separators affects display but not the digest bytes.

References