SHA-256 Hash Generator
Calculate the SHA-256 hash of text or a file. Choose hex or Base64 output and compare against an expected hash.
SHA-256 hash of the text
Calculating…
SHA-256 checksum of a file
Choose a file (up to 100 MB). It is read in your browser and not uploaded.
What SHA-256 is used for
- Verifying downloads: publishers list the SHA-256 checksum so you can confirm a file was not corrupted or tampered with.
- Digital signatures and TLS certificates.
- Blockchains such as Bitcoin, which use SHA-256 for mining and addresses.
- Detecting duplicate files, and creating cache keys.
Example
The SHA-256 hash of the word hello is 2cf24dba5fb0a30e26e83b2ac5b9e29e1b161e5c1fa7425e73043362938b9824. Change one letter and the whole hash changes. The hash of empty text is e3b0c44298fc1c149afbf4c8996fb92427ae41e4649b934ca495991b7852b855.
How the common hashes compare
- MD5: 128 bits, 32 characters. Broken for security; fine for quick checksums.
- SHA-1: 160 bits, 40 characters. Deprecated for security since a collision was shown in 2017.
- SHA-256: 256 bits, 64 characters. Secure and the most common choice today.
- SHA-512: 512 bits, 128 characters. Secure, with a longer output.
Hashing is not encryption
A hash cannot be turned back into the original text, and unlike encryption it has no key. That is why the same text always gives the same hash, and why a hash is good for checking that data has not changed.
How to use the SHA-256 Hash Generator tool
- Type or paste text to see its SHA-256 hash, or choose a file to get its checksum.
- Pick the output format: lowercase hex, uppercase hex or Base64.
- Paste a hash into the Expected hash box to check that it matches, then copy the result.
Frequently asked questions
What is a SHA-256 hash?
SHA-256 turns any input into a fixed 256-bit fingerprint, shown as 64 hexadecimal characters. The same input always gives the same hash, and even a tiny change gives a completely different one.
Can a SHA-256 hash be decrypted?
No. A hash is a one-way function, so it cannot be reversed. Websites that claim to decrypt hashes only look the hash up in a list of known inputs.
Is SHA-256 secure?
Yes. SHA-256 has no known practical attacks and is widely used for file integrity, digital signatures and blockchains. For storing passwords, use a slow password hash such as bcrypt or Argon2 instead.
How do I check a file's SHA-256 checksum?
Choose the file in the file section above and compare the result with the checksum published by the download site. Paste that value into the Expected hash box to see a match message.
Is my text or file uploaded?
No. The hash is calculated in your browser with the Web Crypto API, so your data stays on your device.