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UUID Generator

Generate unique UUIDs (v4) for databases, APIs, and applications. Bulk generation with one-click copying.

Generate UUID v4Bulk generationOne-click copyingCryptographically secureNo server requiredInstant results

Generation Options

UUID v4 Format

xxxxxxxx-xxxx-4xxx-yxxx-xxxxxxxxxxxx
x: Random hexadecimal digit (0-9, a-f)
4: Version number (always 4 for UUID v4)
y: Variant bits (8, 9, a, or b)
Length: 36 characters (32 hex + 4 hyphens)
Entropy: 122 bits of randomness
Collision probability: Negligible (2^61)

Common Use Cases

•Database primary keys and foreign keys
•API request/response tracking
•File names and temporary identifiers
•Session IDs and tokens
•Distributed system correlation IDs
•Unique resource identifiers

How to Use the UUID Generator

  1. 1Click "Generate Single UUID" to create one unique identifier
  2. 2Set the count and click "Generate Bulk" to create multiple UUIDs at once
  3. 3Copy individual UUIDs by clicking the copy button next to each one
  4. 4Use "Copy All", "Copy as Array", or "Copy as CSV" for bulk copying
  5. 5Download UUIDs as TXT or JSON files for use in your projects
  6. 6Toggle auto-generation to automatically create a UUID when you visit the page

Frequently Asked Questions

What is a UUID and why should I use one?

A UUID (Universally Unique Identifier) is a 128-bit number that's virtually guaranteed to be unique across time and space. UUIDs are perfect for database primary keys, API request IDs, file names, and any situation where you need a unique identifier without a central authority.

How unique are UUID v4s really?

UUID v4s have 122 bits of randomness, making the probability of generating two identical UUIDs incredibly small (about 1 in 5.3 x 10^36). For practical purposes, UUID v4s can be considered globally unique without coordination.

What's the difference between UUID versions?

UUID v1 includes timestamp and MAC address (privacy concerns), v3/v5 are name-based using hashing, and v4 is purely random. V4 is most commonly used because it's simple, secure, and doesn't leak any system information.

Can I use UUIDs as database primary keys?

Yes, UUIDs make excellent database primary keys, especially in distributed systems. They eliminate the need for auto-incrementing integers and prevent key collisions when merging databases. However, they're larger than integers and may slightly impact performance in some databases.

Are the generated UUIDs cryptographically secure?

Yes, our UUID generator uses the browser's crypto.getRandomValues() API, which provides cryptographically secure random numbers. This ensures the UUIDs are unpredictable and suitable for security-sensitive applications.

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