SHA-256 Hash Generator

What is SHA-256?

SHA-256 is the most widely used member of the SHA-2 family, published by the NSA in 2001. It maps any input to a 256-bit digest — 64 hexadecimal characters. It is the default hash of the modern web: TLS certificates, software releases, package managers and the Bitcoin blockchain all rely on it.

Example: the SHA-256 hash of hello is 2cf24dba5fb0a30e26e83b2ac5b9e29e1b161e5c1fa7425e73043362938b9824 — the tool above is pre-filled so you can see it live.

Is SHA-256 secure?

Yes. No practical collision or preimage attack against SHA-256 has ever been found, and it is approved by NIST for all security applications. Unless you have a specific reason to pick another algorithm, SHA-256 is the right default for checksums and integrity verification.

Common uses of SHA-256

• File integrity: the checksums published next to downloads are usually SHA-256.
• TLS certificates and signatures: "SHA-256 with RSA" is the classic certificate signature, and JWTs are commonly signed with HMAC-SHA-256.
• Blockchains: Bitcoin mining and block hashing use double SHA-256.

One caveat: plain SHA-256 is far too fast for password storage — use bcrypt, scrypt or Argon2, which are deliberately slow and salted.

Other hash generators

Need a different digest? Pick another algorithm — each has its own page:

Or go back to the Hash Generator homepage to see all five hashes at once.

Why does my hash not match another tool?

Hashes are computed over bytes, not characters, so two inputs that look identical can still produce different digests. The three usual causes:

• A trailing newline. The shell command echo "secret" hashes "secret" plus a line break, while printf %s "secret" (or echo -n) hashes just the word. Text copied out of a terminal often carries that invisible newline.
• Character encoding. This tool encodes your input as UTF-8 before hashing. "café" is 5 bytes in UTF-8 but 4 bytes in Latin-1, so a tool using a different encoding returns a different digest for the same word. Make sure both sides use UTF-8.
• Stray whitespace. Leading or trailing spaces from copy-paste change the input — and therefore the hash. This tool hashes exactly what sits in the box, byte for byte.

Digest sizes at a glance

Every algorithm has a fixed output length, so a quick character count tells you whether a pasted hash is complete or truncated:

Letter case is only display formatting: toggling Uppercase hex does not change the underlying value, and two digests that differ only by case are the same hash.

Frequently asked questions