Hash generator

Checksums for text and files, computed locally. Ctrl+C copies all.

Source

Working…

How to hash text or a file

  1. Add the input

    Type or paste text, or switch to File and drop any file. An empty string is hashed too, which is handy for checking a library against known values.

  2. Choose algorithms and format

    Tick the digests you need from MD5, SHA-1, SHA-256, SHA-384, SHA-512 and CRC32. Switch the output to Base64 or Uppercase, or tick HMAC and enter a key to get keyed hashes.

  3. Copy or compare

    Each digest has its own copy button, and Ctrl+C (Cmd+C on Mac) with nothing selected copies them all, one per line. Paste a published checksum into Compare to see which algorithm it matches.

Good to know

  • Hashing runs in a web worker, so typing and scrolling stay smooth while a large file is processed. Results update about 100 ms after you stop typing.
  • Compare ignores case and accepts hex or base64, so a checksum copied from a download page matches whichever format is shown. The matching row turns green.
  • Text is hashed as UTF-8 bytes with no trailing newline. That matches printf in a terminal, not echo.
  • HMAC applies to MD5 and the SHA family. CRC32 has no keyed form, so it ignores the key.
  • Uppercase only applies to hex output. Base64 keeps its own case because it is part of the value.
  • Nothing leaves your browser. Files are read locally and never uploaded, so it works offline as well.

Questions people ask

Why does my hash differ from the one in the terminal?

Usually a trailing newline: echo adds one, so echo text | sha256sum hashes an extra byte. Use printf '%s' text or echo -n. For files, make sure you compare the same algorithm and that the file was not changed by a line-ending conversion.

Which algorithm should I use?

SHA-256 for anything that matters, such as verifying downloads or signing. MD5 and SHA-1 are fast and still common in older checksum files, but collisions are practical, so do not rely on them for security. CRC32 only detects accidental corruption.

Can I hash a large file?

Yes. Files are read in your browser inside a web worker, so the page stays responsive. MD5 and CRC32 are streamed in chunks; SHA digests read the whole file into memory first, so very large files depend on how much memory the browser can give the tab.

What is HMAC?

A hash keyed with a secret. Only someone who knows the key can produce or check the value, which is how webhooks and API signatures prove a message is genuine. Tick HMAC and type the key; it is used as UTF-8 text.

Is my file uploaded?

No. Text and files are hashed on your device using the Web Crypto API and a local MD5 implementation. Nothing is sent anywhere.