UUID Generator
Generate multiple UUIDv4 identifiers instantly — uppercase or hyphen-free.
The UUID Generator creates version-4 (random) UUIDs on demand — the universally unique identifiers used for database keys, API entities, tracking events and session ids. Generate one or a hundred at a time, with options for uppercase output and hyphen-free format.
A UUIDv4 is a 128-bit value built from cryptographically strong randomness, formatted as 8-4-4-4-12 hex digits. Version 4 means the version nibble is always 4 and the variant bits follow RFC 4122, so every value is instantly recognizable and effectively unique — collisions require roughly 2⁷¹ generations on average, beyond any realistic dataset.
Generation uses crypto.randomUUID where available (all modern browsers) with a standards-compliant fallback, runs entirely locally, and includes copy buttons for individual ids plus copy-all for the whole batch.
5 UUIDv4 values
194508ca-be75-4a46-b3e5-a192c7b27a234a9a95db-e7b0-41ad-8b48-3191d1939040fda5ee49-095e-47d7-a934-c2d760e7a49b945d4566-1fdd-4282-943f-92729fe152c3db6dfa2d-0a83-413f-b24d-956fc85ad47cAdvertisement
How to use the UUID Generator
- Choose how many UUIDs you need (1–100).
- Toggle uppercase and/or remove hyphens if your system requires it.
- Click Generate (or adjust options to auto-refresh).
- Copy individual values with their copy buttons.
- Use 'Copy all' for the complete list, one per line.
Frequently asked questions
What is the difference between a UUID and a GUID?
None technically — GUID is Microsoft's name for the same RFC 4122 format. Both describe the 36-character, hyphenated 128-bit identifiers this generator produces.
How unique is a random UUID really?
Very. Version-4 UUIDs have 122 random bits, so the chance of a collision across a billion generated values is astronomically small (around 10⁻¹⁸). No registry or central server is needed — each machine generates them independently.
Why would I remove the hyphens?
Some storage systems, legacy schemas and API conventions prefer the compact 32-character hex form without hyphens. The same UUID content is represented either way; this generator gives you both formats on demand.
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