Hash Generator

Reference

What is a cryptographic hash?

A cryptographic hash function takes any input and produces a fixed-size fingerprint (digest). Even a single-character change in the input causes a completely different hash — this is called the avalanche effect. Hash functions are one-way (computationally infeasible to reverse) and deterministic (same input always yields the same output).

Algorithms

SHA-1 (160-bit) is deprecated — practical collision attacks exist and NIST recommends against new uses; still found in legacy systems and Git. SHA-256 (256-bit, SHA-2 family) is the modern standard — used in TLS, Bitcoin, and code signing. SHA-384 / SHA-512 (384/512-bit) offer higher security margins for long-term archival, government systems, and applications needing collision resistance beyond 2¹²⁸. All SHA-2 variants are FIPS 180-4 approved.

Common uses

• File integrity: Hash a file before and after transfer — matching digests guarantee the data is unchanged.
• Password storage: Never use SHA-* directly for passwords. Use dedicated password hashing functions like Argon2, bcrypt, or scrypt with salts in production.
• Digital signatures: Hash the document, then sign the hash with a private key — digital signatures prove authenticity without exposing the full document.
• Data deduplication: Identify identical files by comparing hash fingerprints — same hash means identical content.

Next-generation hash functions

SHA-3 (Keccak, standardized in FIPS 202) offers a completely different internal structure from SHA-2, providing defense-in-depth if SHA-2 is ever compromised. BLAKE3 is a modern, parallelizable hash function optimized for speed — significantly faster than SHA-256 on multi-core CPUs. However, neither SHA-3 nor BLAKE3 is available in the Web Crypto API yet. For most applications, SHA-256 remains the standard and is the recommended default.

Privacy

Hashing runs 100% in your browser using the Web Crypto API (crypto.subtle.digest()). No data is ever sent to a server.