UUID v4 Generator — Bulk Random UUIDs
Generate up to 50 random UUID v4 strings. Copy one or copy all. Nothing is uploaded.
What is a UUID?
A UUID (Universally Unique Identifier) is a 128-bit label used to uniquely identify information. The standard format is xxxxxxxx-xxxx-xxxx-xxxx-xxxxxxxxxxxx — 32 hex digits split into 5 groups. Defined in RFC 4122.
UUID v4
Version 4 UUIDs are randomly generated. The 13th character is always 4 (version) and the 17th is 8, 9, a, or b (variant). The remaining 122 bits are random.
Common Uses
- Primary keys in databases
- Session and request identifiers
- File names to avoid collisions
- Idempotency keys for APIs
- Need non-UUID random strings? Try the Random String Generator
- Read more: UUID v4, ULID, and NanoID comparison
Frequently Asked Questions
What is a UUID v4?
A 128-bit random identifier. The 13th character is 4 (version) and 122 bits are random. Format: 8-4-4-4-12 hex digits.
How many UUIDs can I generate at once?
1 to 50 per run. Use Copy All to grab the full list.
Can two UUID v4 values collide?
In practice, no. With 122 random bits, the chance of a collision is negligible for normal app use.
Is UUID the same as GUID?
Yes for most purposes. GUID is the Microsoft name for the same 128-bit identifier. This generator outputs RFC 4122 UUID v4.
Does this UUID generator upload anything?
No. Values are created with crypto.randomUUID in your browser.