UUID Generator
Generate unique identifiers
UUID v4 Generator
Generate one or more random UUIDs and quickly copy or download them for use in your projects.
Min 1 • Max 100
Generate Secure UUID v4 Identifiers for Your Apps & Databases
Use this UUID Generator to create random version 4 UUIDs (Universally Unique Identifiers) for database keys, API tokens, test data, and unique references – directly in your browser.
RFC 4122 v4 Style UUIDs
Generates random version 4 UUIDs in the standard xxxxxxxx-xxxx-4xxx-yxxx-xxxxxxxxxxxx format, ready to plug into your systems and services.
Bulk Generation Support
Generate anywhere from 1 to 100 UUIDs in one click for seeding databases, fixtures, migrations, or config files during development and testing.
Local & Copy-Friendly
All UUIDs are generated in your browser. Copy them to your clipboard or download as a text file for reuse across projects, scripts, or documentation.
What is a UUID v4?
A UUID (Universally Unique Identifier) is a 128-bit value designed to be globally unique. Version 4 UUIDs are generated using random numbers, making them ideal for identifiers that don't rely on a central authority, database sequence, or predictable pattern.
They are widely used for database primary keys, session IDs, resource identifiers in APIs, and anywhere you need a high probability of uniqueness across systems and environments.
How the UUID v4 Generator Works
- When supported, the tool uses the browser's native crypto.randomUUID() API to generate a standards-compliant v4 UUID.
- If that API isn't available, it falls back to a manual implementation that builds a xxxxxxxx-xxxx-4xxx-yxxx-xxxxxxxxxxxx pattern with random hex digits.
- The "4" in the third block indicates version 4, and the "y" nibble is set to one of 8–b to match the RFC 4122 variant bits.
- For bulk generation, the tool repeats this process for the requested count (capped at 100) and lists each UUID on its own line.
How to Use this UUID v4 Generator
- Enter how many UUIDs you want to generate (between 1 and 100).
- Click the Generate button to create a fresh list of UUID v4 values.
- Review the generated list in the output panel. Each UUID appears on its own line in standard string format.
- Use Copy All to copy the entire list to your clipboard, or click Download to save them as a uuids.txt file.
- Paste the UUIDs into your database seeder, config file, test fixtures, or code as needed.
Common Use Cases & Value
- Generating IDs for database records without relying on auto-increment or central coordination.
- Creating unique identifiers for API resources, URLs, or public-facing tokens.
- Seeding test data and fixtures in development and QA environments.
- Assigning unique tokens for background jobs, queues, or distributed tasks.
- Using as correlation IDs in logs and observability pipelines across microservices.
Privacy & Safety Disclaimer
All UUIDs are generated locally in your browser using JavaScript and are not sent to any server. This tool does not log, store, or share your generated identifiers. For highly sensitive production use, you may still prefer to generate UUIDs directly within your backend stack to keep all critical ID creation inside your controlled infrastructure.
FAQ – UUID Generator Tool
1. Are these UUIDs guaranteed to be unique?
UUID v4 values are not mathematically guaranteed to be unique, but the probability of collision is extremely low and acceptable for most real-world applications and system designs.
2. What format are the UUIDs in?
The tool outputs standard lowercase UUID strings like 550e8400-e29b-41d4-a716-446655440000, which match most library and database expectations.
3. Can I use these in production?
Yes, the format matches common UUID libraries. For mission-critical systems, you may still want to generate UUIDs directly from your backend code so that ID generation is centralized and auditable.
4. Is my data sent anywhere?
No. UUIDs are generated entirely in your browser using JavaScript and are not uploaded, logged, or persisted by this tool.