SHA-1, SHA-256, and SHA-512 are computed with crypto.subtle.digest, the browser’s native Web Crypto API — the same audited implementation browsers use for security-sensitive operations elsewhere. MD5 was never part of Web Crypto in any browser, so it’s implemented directly here following RFC 1321, the original specification, byte for byte. All four run synchronously in your browser as you type; nothing is sent to a server.
Hash Generator
Generate MD5, SHA-1, SHA-256, and SHA-512 hashes from text, entirely in your browser.
Hashes update live below — even empty input has a well-defined hash for each algorithm.
MD5
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SHA-1
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SHA-256
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SHA-512
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How these hashes are computed
Frequently asked questions
Is MD5 or SHA-1 safe to use for passwords?
No — both are cryptographically broken for security purposes like password storage, and shouldn't be used to hash passwords, API keys, or anything else where an attacker recovering the original value matters. They're still useful here for checksums, file-integrity verification, and deduplication, where the goal is just detecting whether two things are identical, not keeping a secret.
Does this send my text anywhere?
No. Every hash is computed in your browser — SHA-1, SHA-256, and SHA-512 via the browser's built-in Web Crypto API, and MD5 with a small pure-JavaScript implementation since no browser has ever supported MD5 in Web Crypto. Nothing you type is uploaded or logged.
Why do the same input and algorithm always give the same hash?
That's the entire point of a hash function: it's deterministic (the same input always produces the same output) and one-way (you can't recover the input from the output). If typing "hello" twice gave two different SHA-256 values, the algorithm would be useless for verifying that two files or messages are identical.
What's a hash used for in SEO or web work?
Common uses include verifying a downloaded file matches its publisher's published checksum, generating stable cache-busting keys for static assets so a URL only changes when the file's content actually changes, and detecting duplicate content by comparing content hashes instead of comparing full text.
Which algorithm should I use?
For anything new, SHA-256 is the safe default — it's fast, well-supported, and has no known practical weaknesses. SHA-512 is similar but produces a longer hash. MD5 and SHA-1 are only worth reaching for when you need to match an existing checksum that was already generated with one of them, such as a legacy file hash you're verifying against.