What is a cryptographic hash?

A hash function takes input text and produces a fixed-length string. The same input always produces the same output, but even a tiny change produces a completely different hash.

Which algorithm should I use?

SHA-256 is the most widely used today. SHA-512 offers more security. SHA-1 is considered weak and should not be used for security-sensitive purposes.

Can I reverse a hash to get the original text?

No. Hash functions are one-way. It is computationally infeasible to reverse a SHA-256 or SHA-512 hash.

Is my text sent anywhere?

No. Hashing runs entirely in your browser using the Web Crypto API.

Why use SHA-256 over MD5 or SHA-1?

MD5 and SHA-1 have known collision attacks — different inputs can produce the same hash, breaking security guarantees. SHA-256 has no practical collisions and is the default for HTTPS certificates, blockchain, and modern signing.

When is hashing used in real applications?

File integrity (download checksums), password storage (with bcrypt/argon2 wrappers, never raw SHA), digital signatures, blockchain block IDs, content-addressable storage (Git), and deduplication.

Hash Generator

Developer Tools· 30 tools

Free online cryptographic hash generator. Enter any text and instantly compute SHA-1, SHA-256, and SHA-512 hashes. Results update in real time. Uses the browser's native Web Crypto API — your data never leaves your device.

Input Text

Enter text on the left to generate SHA hashes

Frequently Asked Questions

References

Secure Hash Standard (FIPS 180-4) — NIST

Related Tools

Base64 Encoder / Decoder
Encode text to Base64 or decode Base64 back to plain text. Supports full UTF-8 including emoji. Runs in your browser — data never leaves your device.
UUID Generator
Generate random UUID v4 identifiers instantly. Choose uppercase or lowercase, with or without hyphens. Uses the browser's secure crypto API.
JSON Formatter
Format, validate, and minify JSON in your browser. Pretty-print raw JSON with indentation, catch inline syntax errors, or collapse to one line.

Frequently Asked Questions

References and sources

Related Tools