Key Fingerprint Tool

Generate fingerprints for the public key in an SSL certificate

About Key Fingerprints

A public key fingerprint is a cryptographic hash that uniquely identifies a public key without revealing the key itself. Fingerprints are used for key validation, SSH host verification, and certificate pinning. Our Key Fingerprint Tool extracts the public key from an SSL/TLS certificate and generates fingerprints using MD5, SHA-1, SHA-256, SHA-384, and SHA-512 algorithms, making it easy to verify and compare keys across different formats and systems.

How to Use

Enter the domain name whose certificate public key fingerprint you want to generate.
Click Generate to fetch the certificate and compute fingerprints.
Review the key type, key size, and subject information.
Copy individual fingerprints using the Copy button next to each hash.

Use Cases

Certificate Pinning: Generate SHA-256 fingerprints for use in HTTP Public Key Pinning (HPKP) configurations.
Key Verification: Compare fingerprints across servers to confirm they share the same public key.
Security Audits: Track key fingerprints over time to detect unauthorized certificate or key changes.
SSH Key Management: Generate and compare fingerprints for SSH host key verification and management.

Frequently Asked Questions

Key fingerprints are used to uniquely identify public keys without sharing the full key data. They are commonly used in certificate pinning to prevent man-in-the-middle attacks, SSH host key verification, and ensuring key consistency across load-balanced servers.

SHA-256 is the most widely recommended fingerprint algorithm due to its strong security properties and broad compatibility. SHA-1 is still commonly used but is being phased out due to collision attacks. MD5 should only be used for legacy compatibility.

A certificate fingerprint hashes the entire certificate including metadata, while a key fingerprint hashes only the public key. Key fingerprints remain the same across certificate renewals if the same key pair is reused, making them more stable for long-term identification.

Tips & Best Practices

•Calculate key fingerprints for certificate pinning and verification
•Use fingerprints to verify key authenticity during deployment
•Store fingerprints securely for later comparison
•Compare fingerprints across multiple sources for tamper detection

Technical Details

Calculation: Public key fingerprint computation
Algorithms: SHA-256 and SHA-1 fingerprint calculation
Format: Hex-encoded fingerprint strings
Output: Key fingerprint for pinning and verification