Paste one UUID per line to validate a batch.
This tool works entirely in your browser. Nothing is sent or stored on any server.
Validate one or many UUIDs at once and instantly see which version each one is. Detects UUID versions 1 through 7.
Everything runs locally in your browser — your data never leaves your device.
A UUID is 36 characters long: 32 hexadecimal digits in five groups separated by hyphens, in an 8-4-4-4-12 pattern, like 550e8400-e29b-41d4-a716-446655440000. The 13th digit encodes the version.
Version 1 is time-based and derived from the machine's MAC address. Version 4 is fully random and the most common. Version 7 is timestamp-ordered with random bits, which makes it sortable and database-index friendly — a modern replacement for v4.
For random version 4 UUIDs, collisions are astronomically unlikely: you would need to generate about 2.7 trillion UUIDs before reaching a 50% chance of a single collision. In practice, a v4 UUID can be treated as unique.