UUID Generator

Generate up to 20 cryptographically secure UUID v4 values at once.

Category: Dev Tools

When to use?

Use it whenever you need unique IDs — database record identifiers, API request tracking IDs, or filename collision avoidance. It generates in the browser, ready instantly without a server.

How to use

  • Choose how many UUIDs to generate (up to 20).
  • Click "Generate".
  • Copy the generated UUIDs.

Input Explanation

Choose the count (1–20), case option, and whether to include hyphens.

Calculation Basis

It generates with the browser Web Crypto API (crypto.randomUUID) using cryptographically secure randomness. Generated UUIDs are not sent to a server.

Usage Examples

  • Generate database keys - Pre-generate a unique UUID as a primary key before inserting a record.
  • API request tracking ID - Use as a unique correlation ID per API request.
  • Quick pre-deploy check - Check inputs and output to reduce errors before dev/ops work.

Examples

  • Example: 550e8400-e29b-41d4-a716-446655440000
  • Generate 10 at once → a list of unique IDs for test data

Cautions

  • Generated or formatted output is for reference; test carefully before production use.
  • Specific web-standard specs or framework-only syntax may cause compatibility issues with the output.

Guides

What a UUID is

A UUID (Universally Unique Identifier) is a 128-bit unique identifier in the form xxxxxxxx-xxxx-xxxx-xxxx-xxxxxxxxxxxx, with an extremely low collision chance.

v4 UUID traits

Version 4 UUIDs are randomly generated, used for database keys, session IDs, and filenames. For sortable IDs, consider timestamp-based v1 or v7.

FAQ

How is UUID v4 generated?

With the browser Web Crypto API (crypto.randomUUID) using cryptographically secure randomness.

What is the collision chance?

The theoretical collision probability is extremely low, so it is practically unique.

Can I get uppercase?

An option generates UPPERCASE UUIDs.

Are generated UUIDs stored on a server?

All generation happens only in the browser and is not sent to a server.

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