Random GUID Generator
Generate random GUIDs / UUIDs (version 4) for use as unique identifiers in code, databases, or testing.
Recommended Settings
Pro Tips
- •These are version 4 (random) UUIDs, formatted as 8-4-4-4-12 hex digit groups, the most common GUID format
- •The version and variant bits are set correctly, so these are valid, standards-compliant UUIDs
- •With 122 random bits, the chance of two version-4 UUIDs ever colliding is astronomically small
- •Generate up to 50 at once and copy them all as a newline-separated list
Most Popular
Most users generate a handful of GUIDs at once for seeding test databases or sample data
When to Use This Tool
Generate example UUID primary keys for a database schema or seed data.
Create realistic-looking unique identifiers for testing an application.
Get a random UUID to use as a placeholder ID while developing a feature.
Demonstrate how UUIDs allow unique IDs to be generated without central coordination.
How It Works
Generate 16 cryptographically random bytes for each GUID using the Web Crypto API
Set the version (4) and variant bits as required by the UUID specification
Format the bytes as a standard 8-4-4-4-12 hex string and display the requested number of results
100% Private
Files never leave your device. All processing happens locally in your browser.
Lightning Fast
Powered by Web Crypto API (crypto.getRandomValues), RFC 4122 version 4 UUID format for optimal performance on modern browsers.
Open Source
Built with verified, open-source libraries. Fully transparent.
Frequently Asked Questions
What's the difference between a GUID and a UUID?
They refer to the same concept - GUID is Microsoft's term, UUID is the more general/standardized term (RFC 4122). This tool generates standard version 4 UUIDs, which also work as GUIDs.
Are these guaranteed to be unique?
Not mathematically guaranteed, but with 122 random bits per UUID, the probability of a collision is negligible for virtually any practical use case.
Can I use these in production?
Yes, version 4 UUIDs generated with a cryptographically secure random source are suitable for production use as identifiers.
Is my data sent to a server?
No. Every GUID is generated entirely in your browser.
How many can I generate at once?
Up to 50 at a time, which you can copy individually or all together as a list.