(PHP 5 >= 5.6.0, PHP 7, PHP 8)

openssl_x509_fingerprintCalculates the fingerprint, or digest, of a given X.509 certificate


openssl_x509_fingerprint(OpenSSLCertificate|string $certificate, string $digest_algo = "sha1", bool $binary = false): string|false

openssl_x509_fingerprint() returns the digest of certificate as a string.



See Key/Certificate parameters for a list of valid values.


The digest method or hash algorithm to use, e.g. "sha256", one of openssl_get_md_methods().


When set to true, outputs raw binary data. false outputs lowercase hexits.

Return Values

Returns a string containing the calculated certificate fingerprint as lowercase hexits unless binary is set to true in which case the raw binary representation of the message digest is returned.

Returns false on failure.


Version Description
8.0.0 certificate accepts an OpenSSLCertificate instance now; previously, a resource of type OpenSSL X.509 was accepted.
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User Contributed Notes 1 note

nb at dland dot de
9 years ago
The manual is not constistent at this point. On one hand, it describes the return as digest/fingerprint of a cert, on the other hand it says:
bool openssl_x509_fingerprint( … )

On PHP 5.6.5, I only get the bool return (1 or 0).
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