Dev Tools

Hash Tools

Compute MD5, SHA-1, SHA-256, SHA-512, CRC32, and HMAC checksums, or check a digest against published test vectors. Hashes are not encryption.

12 tools · 100% browser-based · No uploads · No signup

About these Hash tools

Hash tools compute MD5, SHA-1, SHA-256, SHA-512, CRC32, and HMAC in Web Crypto or JS implementations, identify likely hash types, compare digests, checksum files, and convert hex/Base64. The test-vector page only recognizes published RFC/FIPS example strings. It is not a password cracker.

Hashes are one-way fingerprints. They verify integrity and feed HMAC. They are not encryption. MD5 and SHA-1 are broken for collision resistance; do not use them for new security designs. File checksums are still a reasonable way to verify a download matches the published digest.

Tools in this category

How these tools run in your browser

Text is encoded as UTF-8 unless you hash a file's raw bytes. Web Crypto provides SHA-256/512 and HMAC where available. MD5/SHA-1/CRC32 use well-known implementations in JS. Identifier uses length and alphabet heuristics. The test-vector checker hashes a handful of published example strings and compares digests. It does not run a password dictionary.

Common Use Cases

  • Verify a Linux ISO against the published SHA-256
  • Generate HMAC-SHA256 for an API signing test with a throwaway key
  • Guess whether a 32-hex string is MD5 vs something else
  • Compare two checksums without eyeballing
  • Convert a hex digest to Base64 for a header

Common Mistakes

Hashing a string vs a file that contains that string plus a newline yields different digests.
HMAC needs a secret. Pasting production secrets into any website is a process smell even when we do not upload them.
Identifying a hash by length is a guess. Many algorithms share hex length.
CRC32 is for accidental corruption, not adversaries.

Frequently Asked Questions

Can I reverse SHA-256?

Not practically. The test-vector page only recognizes a few published example strings. It will not recover a password. Use a password hashing scheme (Argon2, bcrypt) if you are storing credentials.

Should I store passwords with SHA-256?

No. Use a password hashing scheme (Argon2, bcrypt, scrypt) with salt. See the password storage guide under Security.

Why does my checksum not match?

Wrong algorithm, text vs binary mode, or a truncated copy. Hash the downloaded file, not a zip of the file, unless the publisher hashed the zip.