How to Use the UUID Generator

Select a UUID version (v4 for random, v1 for time-based), then click Generate to create a new UUID. Use the Copy button to copy the result to your clipboard. Your last 5 generated UUIDs are kept in the history section below.

What is a UUID?

A UUID (Universally Unique Identifier) is a 128-bit label used to uniquely identify information in computer systems. They are formatted as 32 hexadecimal digits displayed in five groups separated by hyphens: xxxxxxxx-xxxx-xxxx-xxxx-xxxxxxxxxxxx.

UUID Versions

v4 (Random): Generated using random or pseudo-random numbers. Most commonly used when you just need a unique identifier with no special structure.
v1 (Time-based): Generated using the current timestamp and the machine's MAC address (or a random node ID in browser environments). Useful when you need sortable or traceable IDs.

Common Use Cases

Primary keys for database records
Session tokens and API keys
Idempotency keys for API requests
Unique file names to avoid collisions
Distributed systems where coordination is difficult

FAQ

Are UUIDs truly unique?

UUID v4 has 122 bits of randomness, making collisions astronomically unlikely. For practical purposes, you can treat them as globally unique.

Is my data safe?

Yes. All UUID generation happens in your browser using the Web Crypto API. No data is sent to any server.