Guide
Hash algorithm comparison
Choose hash algorithms by security status and purpose. For modern integrity checks, SHA-256 and SHA-512 are widely supported. Avoid MD5 and SHA-1 for security.
This comparison shows how the same input produces different hash outputs. MD5 is included as a working legacy tool, but it is dangerous for security-sensitive use.
Practical Hash Choices
| Algorithm | Security status | Useful for | Avoid for |
|---|---|---|---|
| MD5 | Broken Legacy / unsafe | Useful for legacy checksum compatibility | Do not use for signatures, certificates, passwords, or tamper-proof integrity |
| SHA-1 | Broken for collision resistance Deprecated | Useful only for legacy compatibility | Do not use for modern security-sensitive workflows |
| SHA-256 | Strong and widely supported Recommended | Good default for integrity checks and signatures | Do not use alone for password storage |
| SHA-512 | Strong and widely supported Recommended | Good for integrity checks, especially on 64-bit platforms | May be less convenient where ecosystem support expects SHA-256 |
| BLAKE2 | Strong Good with caveats | Fast modern hashing where supported | Check ecosystem and compliance requirements before using |
| BLAKE3 | Strong and very fast Very strong, adoption varies | Excellent for modern high-performance hashing | Use only where runtime and tooling support are acceptable |
The comparison is intentionally explicit: we still provide tools for legacy algorithms when legal and useful, but we do not hide their risks.
Privacy And Limitations
The comparison reference is static. The optional hash comparison tool computes MD5 locally and SHA-256 with the browser Web Crypto API.
- Algorithm choice is only one part of secure system design.
- Password storage requires dedicated password hashing algorithms, not fast general-purpose hashes.
- Regulated environments may require specific approved algorithms.
FAQ
Which hash should I use by default?
SHA-256 is a safe default for broad compatibility. SHA-512 is also strong. BLAKE3 is fast and modern where ecosystem support is acceptable.
Should I use SHA-256 for passwords?
No. Use Argon2id, bcrypt, or scrypt. Password hashing needs salts and deliberate slowness against brute-force attacks.
Why are MD5 and SHA-1 marked as weak?
Both have known collision weaknesses that make them unsuitable for modern security-sensitive integrity or signature workflows.
When does BLAKE3 make sense?
BLAKE3 is attractive when speed matters and your runtime ecosystem supports it consistently across services and tooling.
Do faster hashes always mean better performance choices?
Not always. Algorithm choice should balance security requirements, ecosystem compatibility, hardware characteristics, and operational constraints.