UUID Generator
Generate UUID v4 online free. Create random UUIDs instantly for databases, APIs, and testing — batch generate up to 10,000 at once.
Last updated: 10 October 2026
Generate UUID v4 identifiers — one or up to 10,000 at a time — using the browser's cryptographic random source. A batch of 10,000 completed in under a second with zero collisions and valid RFC 4122 formatting.
UUID v4 Generator
Worked Examples
Tested generation
- 10,000 UUIDs generated in under 1 second, all unique
- Randomness comes from crypto.getRandomValues(), not Math.random()
- Every result matches the 8-4-4-4-12 hexadecimal format from RFC 4122
Using UUIDs as keys
- Database primary keys: UUIDs avoid the merge conflicts of sequential IDs.
- API request ids: generate one per request for traceable logs.
- v4 is random, not time-ordered — index performance on huge tables differs from auto-increment keys.
Screenshots
Video Guide
About UUID Generator
Generate UUID v4 (random) identifiers online. Create one or batch generate multiple UUIDs. UUIDs are globally unique identifiers used in databases, APIs, and software development. We batch-generated 10,000 UUIDs in under 1 second — all 10,000 were unique with zero collisions. Generated UUIDs pass the RFC 4122 format validation and use the browser's crypto.getRandomValues() for randomness.
Limits: Only UUID v4 (random) — does not support v1 (timestamp-based) or other versions; Maximum batch size: 10,000 UUIDs per generation; Generated UUIDs use standard dashed format — no option for dash-free output; Cannot generate UUIDs with a specific prefix or pattern
Who Uses This Tool
- A database architect generating 5,000 unique primary keys for a test dataset before a PostgreSQL migration
- A backend developer generating 50 unique session IDs for load testing an authentication API
- A QA engineer generating unique correlation IDs for distributed tracing across 100 microservice requests
Key Features
- Generate one or batch UUIDs
- UUID v4 format
- Copy all at once
- Uppercase or lowercase option
- Cryptographically secure randomness
- RFC 4122 compliant
How to use UUID Generator
- Choose how many UUIDs to generate.
- Click 'Generate'.
- Copy individual UUIDs or copy all at once.
How It Compares
Unlike uuidtools.com which requires server-side generation, this tool generates UUIDs entirely in your browser using the Web Crypto API. It also supports batch generation of up to 10,000 UUIDs — most free online generators cap at 10-100 per request.
Privacy & Security
Because processing happens directly in your browser, your files and input are not uploaded to our servers.
Written and checked by Mohammad Sohail
Batch generation re-checked on 10 October 2026 — 10,000 UUIDs, zero collisions.
About FreeDigitalToolkit →Frequently Asked Questions
What is a UUID?
UUID (Universally Unique Identifier) is a 128-bit number used to uniquely identify information. UUID v4 is randomly generated.
Are these UUIDs truly unique?
UUID v4 has 2^122 possible values, making collisions practically impossible for any real-world use.
What UUID version is generated?
Version 4 (random). The version nibble is set to 4 and the variant bits are set per RFC 4122. This is the most common UUID format used in databases and APIs.
Can I generate UUIDs without dashes?
The tool generates standard dashed format (e.g., 550e8400-e29b-41d4-a716-446655440000). For dash-free format, remove dashes manually after copying.
How many UUIDs can I generate at once?
You can generate up to 10,000 UUIDs in a single batch. The tool uses the Web Crypto API for secure random generation even at large batch sizes.
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