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UUID Generator Online

Generate cryptographically secure UUID v4 values instantly. Free, bulk generation up to 100 UUIDs, one-click copy — runs entirely in your browser.

Count:
e2669879-1320-4d45-8498-84b589489377

Generated with crypto.randomUUID() — cryptographically secure · RFC 4122 UUID v4

What is UUID Generator?

A UUID (Universally Unique Identifier) is a 128-bit label used to uniquely identify information in computer systems. The standard format displays it as 32 hexadecimal digits split into 5 groups: xxxxxxxx-xxxx-xxxx-xxxx-xxxxxxxxxxxx. UUIDs are designed to be generated without a central registry, meaning any computer can create a new UUID with near-zero probability of collision with any other UUID ever created.

UUID version 4 (UUID v4) is the most commonly used variant, generating all 128 bits randomly except for 4 version bits and 2 variant bits. With 122 bits of entropy, the number of possible UUID v4 values is 5.3 × 10^36 — a number so large that generating billions of UUIDs per second for millions of years would still be statistically unlikely to produce a duplicate.

UUIDs are essential in modern software development: used as primary keys in distributed databases (avoiding the need for auto-increment coordination), session identifiers, idempotency keys in APIs, file names, correlation IDs for distributed tracing, and anywhere a unique identifier is needed across multiple systems or services.

How to Use

  1. 1

    Set the count (optional)

    Enter how many UUIDs you need — from 1 to 100. The default is 1.

  2. 2

    Click Generate

    Click the Generate button to create cryptographically secure UUIDs instantly.

  3. 3

    Copy your UUID(s)

    Click Copy next to any individual UUID, or use the Copy All button to copy all generated UUIDs at once.

Features

  • Generates UUID version 4 (random) per RFC 4122
  • Uses crypto.randomUUID() — cryptographically secure
  • Bulk generation: up to 100 UUIDs at once
  • One-click copy per UUID or copy all
  • Works entirely in your browser
  • No data sent to any server
  • Free with no limits or sign-up
  • Instant generation with zero latency

Frequently Asked Questions

QWhat is a UUID?
UUID (Universally Unique Identifier) is a 128-bit label used to uniquely identify objects in computer systems. The standard format is 8-4-4-4-12 hexadecimal characters separated by hyphens.
QWhat is UUID v4?
UUID version 4 is randomly generated. It uses random or pseudo-random numbers for all 128 bits (with 4 bits for the version and 2 bits for the variant). It is the most commonly used UUID version.
QAre these UUIDs truly unique?
UUID v4 has 122 bits of randomness, resulting in 5.3 × 10^36 possible values. The probability of a collision is astronomically small — effectively zero for any practical use.
QIs it safe to use these UUIDs in production?
Yes. This tool uses the Web Crypto API (crypto.randomUUID), which is the same cryptographically secure source used by modern browsers and servers.
QWhat are common use cases for UUIDs?
UUIDs are used as primary keys in databases, session identifiers, correlation IDs for distributed tracing, file names, API keys, and anywhere a unique identifier is needed without a central registry.