UUID Generator
A UUID generator creates Universally Unique Identifiers version 4, 128-bit identifiers used in software development. Each UUID is statistically unique across space and time, ideal for database primary keys, API tokens, session identifiers, and any situation requiring unique identifiers without centralized authority. Generate single or bulk UUIDs with each independently random. Version 4 UUIDs use 122 bits of cryptographically strong random data in standard 8-4-4-4-12 hexadecimal format. Uses Web Crypto API for true randomness. Follows RFC 4122 with version and variant bits embedded. Each UUID has 32 hex characters grouped by hyphens. Collision probability is approximately 1 in 5.3 undecillion. Creating database primary keys for distributed systems. Generating API keys and auth tokens. Producing session identifiers. Creating order and transaction IDs. Generating request tracking IDs. Creating entity identifiers in microservices. Producing installation and device IDs. Generating correlation IDs for distributed tracing. Consider UUID v7 for time-sortable identifiers in databases. Store UUIDs as binary(16) instead of char(36) for performance. Be aware of index fragmentation with random UUIDs in MySQL. For user-facing IDs, consider shorter formats like NanoID. Related tools: Password Generator, Random Number Generator, QR Code Generator, Random Color Generator, Raffle / Picker Wheel. Browse all 123 free tools on the KitCraft home page.