UUID & Hash Generator
Generate UUID v4 identifiers and compute cryptographic hashes instantly.
UUID v4 Generator
Hash Generator
About this tool
UUIDs (Universally Unique Identifiers) are 128-bit values used to uniquely identify resources without a central authority. Cryptographic hash functions produce fixed-length digests from arbitrary input.
UUIDs are used for database primary keys, session IDs, and API resource identifiers. Hashes are used for data integrity verification, checksums, and digital signatures.
Frequently asked questions
What is the difference between UUID v1 and UUID v4?
UUID v1 uses the current timestamp and MAC address — it is time-ordered but reveals creation metadata. UUID v4 is randomly generated, reveals nothing about its origin, and is preferred for security.
Is MD5 safe for passwords?
No. MD5 is fast and has known collision vulnerabilities. Use bcrypt, scrypt, or Argon2 for passwords. MD5 is only appropriate for non-security checksums.
What is the difference between SHA-256 and SHA-512?
SHA-256 produces a 256-bit digest. SHA-512 produces a 512-bit digest and is faster on 64-bit processors. For most purposes SHA-256 is sufficient.