UUID Generator
Generate RFC 4122 v4 UUIDs in bulk, with formatting options for hyphens, case, braces and plain-vs-CSV output.
Updated September 2026 · Written and verified by Akash Pandey
UUID Generator
How to use the UUID generator
- Choose how many UUIDs to generate.
- Set formatting: hyphens on/off, uppercase, and wrap in braces.
- Pick plain (one per line) or CSV/JSON array output for code.
- Click Generate and copy.
Frequently asked questions
What is a UUID?
A universally unique identifier: a 128-bit value formatted as 32 hex digits grouped by hyphens (8-4-4-4-12), with version and variant bits set - used to identify records, entities and requests without coordination.
Which version is generated?
v4, which uses 122 bits of cryptographic randomness from crypto.randomUUID or the generated-v4 algorithm - effectively collision-free for practical purposes.
Can two UUIDs collide?
With 122 random bits, the odds of a collision across an entire planet's worth of instances are negligible. v4 relies on randomness, not on global coordination.
Why would I remove hyphens?
Some databases (and URLs) prefer the 32-hex form. It decodes to the same 128-bit value; only presentation changes.
What is a UUID useful for?
Database primary keys, traceable API request IDs, tracking IDs, and anywhere you need an identifier that does not require a central registry.
Is the generator private?
Yes - UUIDs are created locally with browser cryptography; nothing is transmitted.
What is the probability of a UUID v4 collision?
The collision probability is so vanishingly small (1 in billions of trillions) that UUIDs are considered universally unique for all practical applications.
Can I generate bulk UUIDs in uppercase or lowercase?
Yes. You can generate batches of up to 100 UUIDs at a time and format them in uppercase or lowercase.