Generate universally unique identifiers instantly
UUID (Universally Unique Identifier) is a 128-bit identifier formatted as a 36-character string (8-4-4-4-12). Used for unique IDs in databases, APIs, and software.
UUID v1 uses timestamp and machine node ID. UUID v4 uses cryptographically random numbers (most common). UUID v7 uses Unix timestamp for better sorting performance.
Yes, generate from 1 to 100 UUIDs in a single click. Useful for batch operations and testing.
UUID v4 works but causes index fragmentation in B-tree databases due to randomness. UUID v7 is preferred for primary keys because its timestamp prefix produces sequential values, improving insert performance and reducing storage overhead.
Statistically, yes. UUID v4 has 122 random bits, yielding roughly 5.3 × 10^36 possible values — collision probability is vanishingly small. UUID v1 includes a node identifier, and v7 combines timestamp with randomness, making duplicates practically impossible.