SHA-256 Hash Generator
| Algorithm | Digest length | First 32 chars of "hello world" |
|---|---|---|
| SHA-1 | 160 bits (40 hex) | 2aae6c35c94fcfb415dbe95f408b9ce9 |
| SHA-256 | 256 bits (64 hex) | b94d27b9934d3e08a52e52d7da7dabfa |
| SHA-384 | 384 bits (96 hex) | fdbd8e75a67f29f701a4e040385e2e23 |
| SHA-512 | 512 bits (128 hex) | 309ecc489c12d6eb4cc40f50c902f2b4 |
The SHA-256 hash is a one-way fingerprint: the same input always produces the same 256-bit output, but the output reveals nothing about the input. This tool computes it entirely in your browser using the Web Crypto API - no server round-trip, no network request, the text never leaves the page.
The table below shows the known SHA-256 values of common test strings, so you can verify the tool is working correctly before trusting it with real data.
How to use
- Type or paste text; the SHA-256 digest appears instantly as the page renders it.
- Copy the hash for use in integrity checks, commit messages or API signatures.
- Use the hello world chip to verify the tool matches the published standard test vector.
Frequently asked questions
What is the SHA-256 of the empty string?
e3b0c44298fc1c149afbf4c8996fb92427ae41e4649b934ca495991b7852b855. This is the most famous test vector in cryptography - every correct implementation produces exactly this for zero-length input. If you see it in your output, your input was empty.
Can I use SHA-256 to store passwords?
No. SHA-256 is a fast general-purpose hash designed for integrity checking. Password storage needs a deliberately slow, salted construction - bcrypt, scrypt or Argon2 - because attackers can compute trillions of SHA-256 hashes per second on GPUs. The NIST SP 800-132 guidelines cover password hashing specifically.
What is the difference between SHA-256 and SHA-512?
The internal state size: SHA-256 uses 256-bit words and produces 64 hex characters; SHA-512 uses 512-bit words and produces 128 hex characters. SHA-512 is actually faster on 64-bit processors because it processes larger chunks. Both are currently secure per NIST.
What does collision-resistant mean?
No two known inputs produce the same SHA-256 output. This is different from unbreakable - mathematically, collisions must exist because the input space is larger than the output space. But no one has ever found one for SHA-256, despite decades of effort. SHA-1 lost this property in 2017.