SHA-256 Hash Generator
Compute FIPS-standard SHA-256, SHA-384, and SHA-512 hashes instantly using the browser's native Web Crypto API. Support for salting, HMAC keys, and direct file integrity checks.
Understanding SHA-2 Cryptographic Hashes & Security Standards
What Is SHA-256 and How Does It Work?
SHA-256 (Secure Hash Algorithm 256-bit) is a member of the SHA-2 family designed by the National Security Agency (NSA) and published by NIST in 2001 under FIPS PUB 180-4.
It produces a fixed-size 256-bit (32-byte) message digest regardless of input length. Because SHA-256 possesses strong preimage resistance and collision resistance (no practical collision has ever been discovered), it is widely used in TLS/SSL certificates, Bitcoin proof-of-work, Git commit signatures, and file checksum verification.
SHA-256 vs SHA-384 vs SHA-512: Which Should You Use?
While all belong to the SHA-2 family, they differ in output size and internal word architecture:
- SHA-256: Operates on 32-bit words, produces 64 hexadecimal characters. Fast on 32-bit architectures and standard for most protocols.
- SHA-384: Truncated 512-bit state, resistant to length extension attacks, common in high-assurance TLS suites.
- SHA-512: Operates on 64-bit words, produces 128 hexadecimal characters. Frequently faster on 64-bit CPUs than SHA-256 due to instruction alignment.