Hash Generator
Generate a cryptographic digest of any text using your browser's own Web Crypto implementation — the same underlying primitives a server would use.
100% private — everything runs in your browser, nothing is ever uploaded.
What this tool does
A downloaded file comes with a SHA-256 checksum, or a colleague needs a stable fingerprint of a string to confirm two systems hold identical data. A hash is a fixed-length digest: the same input always produces the same output, and a single changed character produces a completely different one. This tool computes SHA-1, SHA-256, SHA-384 and SHA-512 digests of any text using the Web Crypto implementation built into your browser, the same underlying primitives a server would use. It is useful for verifying integrity, checking that an integration produced the expected canonical string, or generating a deterministic identifier for a cache key. A hash is one-way, so it cannot be reversed to recover the input, and it is not a suitable way to store a password on its own.
How to use it in three steps
- Paste the text you want to hash. Whitespace and line endings count as characters, so copy exactly what the other system will hash.
- Tick the algorithms you need. SHA-1 and SHA-256 are selected by default; add SHA-384 or SHA-512 if the checksum you are matching uses a longer digest.
- Press Generate and compare the lower-case hexadecimal output with the value you were given. A mismatch usually means an invisible difference such as a trailing newline. Hash the exact bytes the other system hashed, including invisible trailing whitespace, or the comparison will fail.
Questions people ask
Which algorithm should I choose?
Match whichever the other side used. SHA-256 is the common default for modern integrity checks; SHA-1 still appears in legacy systems but should not be chosen for new security work; SHA-384 and SHA-512 simply produce longer digests.
Why does my hash not match the file's checksum?
This tool hashes text you paste, not a binary file's bytes. For a file checksum, use your operating system's hashing command. Also check whether the other side hashed a string with a trailing newline or different capitalisation.
Can a hash be reversed to get the original text?
No. A cryptographic digest is one-way by design. If you need to recover the original, you want encoding such as Base64, not a hash; if you need to protect a password, you want a slow password hashing function with a salt.
Does the same text always produce the same digest?
Yes, for a given algorithm and the same input bytes. That determinism is what makes hashes useful for integrity checks and cache keys. It is also why a plain unsalted hash of a common password is easy to recognise in a leaked dataset.
Privacy: The text is hashed by your browser's built-in crypto API entirely on your device; neither the input nor the resulting digest is sent anywhere or retained after the page closes.
How to use it
- Paste the text you want to hash.
- Tick the algorithms you want — SHA-1 and SHA-256 are on by default.
- Press Generate. Each digest is shown in lower-case hexadecimal.
Why it stays private
People hash passwords, licence keys and tokens here. Those inputs are among the most sensitive strings there are, and hashing them on a remote server would defeat the purpose entirely, so this runs in the page.
Questions
Which algorithm should I use?
SHA-256 for almost everything. SHA-1 is included for compatibility with older systems and for checking existing checksums, but it is no longer collision-resistant and should not be used for anything new. SHA-384 and SHA-512 are available when a system specifies them.
Why does this need HTTPS?
The Web Crypto API, which provides these primitives, is only available in a secure context. On an HTTPS page — or on localhost — it works. On a plain HTTP page the browser hides it, and the tool will say so.
Can I reverse a hash?
No. A hash is a one-way function by design. For short or predictable inputs an attacker can try candidate values until one matches, which is why passwords should be stored with a slow, salted algorithm such as bcrypt or Argon2 rather than a plain hash.