UUID v4 Generator
Generate up to 1,000 random version 4 UUIDs at once using a cryptographically secure random source, in lowercase, uppercase or without hyphens.
Runs on your device
Result
Results appear here after you select “Generate”.
What it does
Version 4 UUIDs are 122 random bits, suitable for database keys, idempotency keys and test fixtures. Values come from crypto.getRandomValues, not Math.random.
How to use it
- Choose how many UUIDs you need.
- Pick the format.
- Generate, then copy or download the list.
Example
The example fills in realistic values and runs the tool. Select Try an example above to see it.
When it helps
- Seeding test data.
- Creating idempotency keys for API calls.
- Generating identifiers for config files.
Questions
Can two generated UUIDs collide?
In practice no. You would need around 2.7 quintillion UUIDs for a 50% chance of a single duplicate.
Are these UUIDs sortable by time?
No. Version 4 is random. If you need time ordering, use UUID v7 in your application.
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