Which algorithm should I use?

SHA-256 is a solid general-purpose default today. SHA-1 is considered broken for security-sensitive uses, though still occasionally used for non-security checksums.

Why do longer algorithms produce longer output?

Each algorithm is designed to produce a fixed digest length — SHA-512 uses a larger internal state and produces longer output than SHA-256, generally offering a larger security margin.

Why does the input text change every digest completely?

That's the avalanche effect, a deliberate design property of cryptographic hash functions — even a one-character change in input should produce a completely different, unpredictable-looking digest.

Are these algorithms officially standardized?

Yes — SHA-1 through SHA-512 are specified in NIST's Federal Information Processing Standard FIPS 180-4, the U.S. government's secure hash standard.

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Developer

Hash Generator

SHA-1, SHA-256, SHA-384, and SHA-512 digests.

🔒 Runs entirely in your browser — nothing here is ever uploaded

About the Hash Generator

Generates SHA-1, SHA-256, SHA-384, and SHA-512 cryptographic hash digests of any text, computed using your browser's built-in Web Crypto API.

How to use it

Enter or paste text into the Input text field.
Read and copy each algorithm's digest below — they update as you type.

Formula

A cryptographic hash function takes input of any length and produces a fixed-length digest, designed so a tiny change in input produces a completely different output.

Worked example

The text 'CalcoTools toolkit' produces a distinct 64-character SHA-256 hex digest — retyping the exact same text always reproduces the identical hash.

Recommendations

• SHA-256 is a solid general-purpose choice today; SHA-1 is considered cryptographically weak for security purposes, though included here for compatibility checks.
• Hashes are one-way — there's no reversing a hash back into the original text, which is exactly what makes them useful for verification without storing the original.
• Useful for checking file integrity: identical hashes from two files effectively guarantee identical contents.

Frequently asked questions

No — cryptographic hashes are intentionally one-way. The only practical 'reversal' is guessing inputs and hashing them until one matches, infeasible for anything reasonably complex.

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Sources

NIST FIPS PUB 180-4 — Secure Hash Standard (SHS) — accessed 2026-08-20