About this tool
What is a hash?
A hash function turns any input into a fixed-size fingerprint (MD5: 32 hex chars, SHA-256: 64). The same input always gives the same output, tiny input changes avalanche into totally different digests, and reversing is computationally infeasible. Uses: integrity checks, deduplication, Git-style content addressing.
How to use it
- Paste text and pick an algorithm (SHA-256 default).
- Compare against a published checksum to verify integrity.
- Hash files with the file variant for downloads and ISOs.
Examples
- Verifying a download: recompute SHA-256 and compare with the vendor’s published value.
- Fingerprinting records to detect duplicates in a dataset.
- Checksumming config files before and after a change window.
Important limitations
- MD5 and SHA-1 are broken for collision resistance — fine for checksums, never for security.
- Hashes are not encryption and not passwords storage: passwords need slow, salted functions like bcrypt or Argon2.
- A matching hash proves integrity, not authenticity — pair with signatures where origin matters.
Privacy
Hashing is local. Note that hashing does not anonymize short or guessable inputs — they can be brute-forced back.
Frequently asked questions
MD5 vs SHA-256?
SHA-256 for anything that matters; MD5 only for legacy checksum compatibility.
Can I “decrypt” a hash?
No — but attackers guess common inputs and compare, which is why passwords need bcrypt, not SHA-256.
Why do two tools show different hashes?
Usually encoding differences (UTF-8 vs UTF-16) or trailing newlines. Normalize input first.