UUID Generator
Generate random UUID v4 values instantly. 100% private, nothing sent anywhere.
A UUID (Universally Unique Identifier) is a 128-bit random value used almost everywhere in software to identify things — database records, API keys, session tokens, file names — without needing a central authority to guarantee uniqueness. This tool generates UUID version 4 (random) values, the most commonly used variant.
Generation happens entirely in your browser using the Web Crypto API's cryptographically secure random number generator — the same source browsers use for security-sensitive operations — so the values are suitable for real use, not just testing.
Step-by-step instructions
- 1
Choose how many
Set the count (1-50) and toggle hyphens or uppercase formatting if needed.
- 2
Generate
UUIDs appear instantly — click 'Regenerate' anytime for a fresh batch.
- 3
Copy
Click any single UUID to copy it, or use 'Copy all' to grab the whole list at once.
Common use cases
Database primary keys
UUIDs avoid collision issues that auto-incrementing IDs can have across distributed systems.
API testing
Generate realistic-looking unique IDs for test requests and mock data.
File and session naming
Guarantee unique file names or session tokens without checking against existing ones.
Tips for best results
- UUID v4 values are randomly generated and not meant to be sequential or sortable — if you need time-ordered IDs, look into ULID or UUID v7 instead.
Frequently asked questions
Are these UUIDs actually unique?
The odds of two random UUID v4 values colliding are astronomically low (about 1 in 2^122) — safe for virtually any real-world use.
Does this tool store or send my UUIDs anywhere?
No — generation happens entirely in your browser using the Web Crypto API; nothing is sent to a server.
What's the difference between UUID and GUID?
They're effectively the same thing — GUID is Microsoft's term for the same UUID standard.