UUID Generator
Generate UUID v4 identifiers using crypto.randomUUID(). Batch generate up to 100, validate existing UUIDs. All processing happens in your browser.
Generate UUIDs
Validate UUID
How to Generate UUIDs
- 1
Click Generate
Generate a single UUID v4 using your browser's cryptographic random number generator.
- 2
Batch Generate
Enter a count (1-100) to generate multiple UUIDs at once.
- 3
Configure Format
Toggle uppercase/lowercase and with/without hyphens.
- 4
Copy or Validate
Copy UUIDs to clipboard or paste an existing UUID to validate its format.
About UUIDs
A UUID (Universally Unique Identifier) is a 128-bit identifier guaranteed to be unique across all devices and time without a central authority. UUID v4, the most widely used version, is generated from random numbers with a collision probability of less than 1 in 2^122. UUIDs are the standard for distributed systems, microservices, and any application needing globally unique identifiers.
UUIDs follow the format xxxxxxxx-xxxx-4xxx-yxxx-xxxxxxxxxxxx per RFC 4122. This format is natively supported by PostgreSQL (uuid type), MySQL, MongoDB, and virtually every modern programming language including Java, Python, Go, C#, and JavaScript.
ToolPix's UUID generator uses the Web Crypto API (crypto.randomUUID()) for cryptographically secure generation. Unlike Math.random()-based generators, the Web Crypto API draws from the OS entropy pool, making these UUIDs suitable for session tokens, API keys, and correlation IDs.
Generate single UUIDs or batch up to 100 at once, toggle uppercase/lowercase, and choose with or without hyphens. The built-in validator checks format and detects version. All generation happens in your browser — no UUIDs are logged or transmitted to any server.
Key Features
Common Use Cases
- •Generate unique identifiers for database records
- •Create session IDs and API keys
- •Generate unique filenames for uploads
- •Create tracking IDs for analytics and logging
- •Generate correlation IDs for distributed systems
Frequently Asked Questions
Are UUIDs truly unique?
UUID v4 uses 122 random bits, giving a collision probability of less than 1 in 5.3×10^36. You would need to generate 1 billion UUIDs per second for 85 years to have a 50% chance of one collision.
What is the difference between UUID versions?
v1 uses timestamp + MAC address, v3/v5 use name-based hashing, and v4 (most common) uses random numbers. This tool generates v4, which is the recommended choice for most applications.
Can UUIDs be used as database primary keys?
Yes. UUIDs are widely used as primary keys, especially in distributed systems. They are slightly larger than auto-increment integers but eliminate ID collision risks across multiple databases.
Are the generated UUIDs secure?
Yes. They are generated using the Web Crypto API (crypto.randomUUID()), which provides cryptographically secure random numbers suitable for security-sensitive applications.
Is this UUID generator free to use?
Yes. ToolPix's UUID generator is completely free with no usage limits, no account required, and no ads blocking the interface. Generate as many UUIDs as you need.
Can I use this tool on my phone or tablet?
Yes. The generator works on all modern browsers including mobile Safari and Chrome for Android. The responsive design adapts to any screen size for comfortable use on the go.
Do you store or log the generated UUIDs?
No. All UUIDs are generated entirely in your browser using the Web Crypto API. Nothing is sent to or stored on any server, ensuring complete privacy.
Should I use UUIDs or auto-increment IDs?
UUIDs are ideal for distributed systems, API-exposed IDs, and multi-database architectures where collision avoidance matters. Auto-increment integers are more storage-efficient and faster to index but can expose record counts and cause conflicts when merging databases.