The browser's built-in crypto API does not support MD5, so it would require a separate library. MD5 also has practical collision attacks and should not be used for security, so it was left out. Use SHA-256 for integrity checks.

Is SHA-1 safe to use?

Only for matching values in an existing system. SHA-1 has demonstrated collision attacks and is not suitable for anything new. Use SHA-256 or stronger for new designs.

Not yet — this tool takes text input only. For file checksums, your operating system's command (shasum on macOS and Linux, certutil on Windows) is the reliable route.

Can two UUIDs collide?

Version 4 UUIDs fill 122 bits with random data generated by the browser's cryptographic random source. At any realistic scale the chance of a collision is negligible.

Is my input sent to a server?

No. Hashing and UUID generation both happen in your browser. That said, it is wise not to paste real passwords or production secrets into any web tool.

SHA-256 Hash Generator - SHA-1, 384, 512 and UUID Generator

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Developer Tools

Text to hash

Generate UUIDs

Count

Hash and UUID features

SHA Hash Generator — computes SHA-1, SHA-256, SHA-384 and SHA-512 of your input at the same time and shows them in hex, updating as you type. UUID Generator — creates up to 50 RFC 4122 version 4 UUIDs at once, with per-value and bulk copy. Everything is computed with the browser's built-in Web Crypto API, so your input never leaves the page.

How to use

1. Type or paste the text you want to hash. 2. All four SHA digests appear immediately below. 3. Use the copy button next to the algorithm you need. 4. For UUIDs, pick a count further down and press Generate.

When to use it

• Produce a reference value to compare against a download checksum • Check an intermediate value while building an API signature • Generate cache keys or identifiers • Create UUIDs in bulk for test data • Prepare UUIDs for use as database primary keys

Frequently Asked Questions

Q. Why is MD5 missing?: A. The browser's built-in crypto API does not support MD5, so it would require a separate library. MD5 also has practical collision attacks and should not be used for security, so it was left out. Use SHA-256 for integrity checks.
Q. Is SHA-1 safe to use?: A. Only for matching values in an existing system. SHA-1 has demonstrated collision attacks and is not suitable for anything new. Use SHA-256 or stronger for new designs.
Q. Can I hash a file?: A. Not yet — this tool takes text input only. For file checksums, your operating system's command (shasum on macOS and Linux, certutil on Windows) is the reliable route.
Q. Can two UUIDs collide?: A. Version 4 UUIDs fill 122 bits with random data generated by the browser's cryptographic random source. At any realistic scale the chance of a collision is negligible.
Q. Is my input sent to a server?: A. No. Hashing and UUID generation both happen in your browser. That said, it is wise not to paste real passwords or production secrets into any web tool.