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UUID Generator

Generate random UUIDs (v4). Unique identifiers for databases, APIs, and distributed systems. Uses cryptographically secure random generation. Free UUID generator.

UUID generator

Click "Generate UUID" to create your first UUID

What is this?

A UUID (Universally Unique Identifier) is a 128-bit identifier, typically shown as 8-4-4-4-12 hex digits (e.g., 550e8400-e29b-41d4-a716-446655440000). Version 4 UUIDs use random values. The chance of collision is astronomically low—you can generate billions without overlap. UUIDs work in distributed systems without coordination. No central authority assigns them. The generator uses cryptographically secure random numbers when available. Use UUIDs when you need globally unique identifiers, when sequential IDs would expose information, or when merging data from multiple sources. Standard format is widely supported.

When to use

Use for database primary keys, API tokens, distributed systems, or when you need globally unique IDs without a central authority. Example: Generate IDs for new records. Avoid exposing sequential IDs. Developers create unique identifiers for records. APIs use UUIDs for resource IDs. Distributed systems avoid ID collision. Replace sequential IDs with UUIDs for security. Generate multiple at once for testing. Essential for modern application design. Copy and paste into your code or database. No registration or coordination needed.

How to use

Click "Generate UUID" to create a single UUID, or "Generate 5 UUIDs" for multiple. Each UUID is a version 4 (random) UUID in standard format (8-4-4-4-12 hexadecimal digits).

UUID Format
UUIDs follow the format: xxxxxxxx-xxxx-4xxx-yxxx-xxxxxxxxxxxx where x is a hexadecimal digit and y is one of 8, 9, A, or B.

Frequently asked questions

What is a UUID?
UUID (Universally Unique Identifier) is a 128-bit identifier used to uniquely identify resources. UUIDs are standardized and widely used in databases, APIs, and distributed systems.
What version of UUID does this generate?
This tool generates UUID v4 (random UUIDs). Version 4 UUIDs use random or pseudo-random numbers and are the most common type used in applications.
Are UUIDs guaranteed to be unique?
UUIDs are designed to be unique with an extremely low probability of collision. For practical purposes, they can be considered unique, especially when generated using cryptographically secure random number generators.
When should I use UUIDs?
Use UUIDs when you need globally unique identifiers without a central authority, for distributed systems, database primary keys, API tokens, or when you want to avoid exposing sequential IDs.

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