UUID Generator

By the FastFreeTools Editorial Team · Last reviewed: May 2026 · See our Editorial Policy for methodology, sourcing, and disclaimers.

Generate cryptographically secure v4 UUIDs. Bulk generation support for databases and applications.

About this tool

UUIDs (Universally Unique Identifiers) are 128-bit identifiers used extensively in software development for database primary keys, API identifiers, session tokens, and distributed systems. Version 4 UUIDs are randomly generated, making collisions statistically impossible (the probability is astronomically low). Our UUID Generator creates cryptographically secure v4 UUIDs using the Web Crypto API, with support for bulk generation of up to 100 UUIDs at once. Developers use this daily for generating test data, creating unique identifiers for database records, and setting up distributed system configurations.

How to use UUID Generator

Click 'Generate' to create a new UUID v4.
Use the bulk generator to create multiple UUIDs at once.
Click on any UUID to copy it to your clipboard.
Use the generated UUIDs in your database, API, or application.

Tips & best practices

UUID v4 is randomly generated and suitable for most use cases.
The probability of a UUID collision is astronomically low.
UUIDs are 36 characters long including hyphens (128 bits).
Use lowercase UUIDs for consistency in databases and APIs.

Common use cases

Generating primary keys for database records.
Creating unique identifiers for API resources.
Setting up test data with realistic unique IDs.
Generating session tokens and correlation IDs.

Privacy

This tool runs entirely in your browser. We do not upload, store, log, or process your input on any server. Open your browser's DevTools Network tab to verify — there is no outbound request with your data. See our Privacy Policy for details.

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