About this hash generator
A hash function turns any input into a fixed-length fingerprint. Feed it one character or a whole book, and you get back a string of the same size. Change a single byte of the input and the output changes completely. This tool computes that fingerprint with SHA-256, SHA-1, SHA-512, or MD5, entirely in your browser, so the text you paste never leaves your machine.
The SHA algorithms run through the browser’s built-in Web Crypto engine, which is the same fast, audited implementation your operating system trusts. MD5 is computed in JavaScript because browsers deliberately leave it out of Web Crypto, for a reason worth understanding.
Which one should you use?
For anything security-related, use SHA-256. It is the modern default: fast, widely supported, and with no known practical way to forge a collision. SHA-512 is its bigger sibling, useful when you specifically want a longer digest. SHA-1 and MD5 are both broken for security. Researchers can craft two different inputs with the same SHA-1 or MD5 hash, so never use them to verify signatures, store passwords, or protect anything that matters.
They are still fine for non-security jobs. MD5 in particular remains common as a quick checksum to spot accidental file corruption or to deduplicate data, where nobody is actively trying to trick you. That is why the tool still offers it.
What a hash cannot do
Hashing is one-way. You cannot turn a hash back into the original text, and this tool has no “decode” button because none is possible. A hash also does not encrypt anything, since it does not hide the input, it summarizes it. If two people hash the same text with the same algorithm, they get the same result every time, which is exactly what makes hashes useful for comparing and verifying data.
Read how hashing works for the concepts behind the output. If you are deciding between algorithms, our SHA-256 versus MD5 comparison covers the practical tradeoffs.