UUID Generator
Generate random version 4 UUIDs for development, testing, or database keys.
About This Tool
This tool generates version 4 UUIDs (universally unique identifiers) using your browser's built-in crypto.randomUUID function, which follows the standard UUID v4 format used across databases and APIs.
How It Works
- Set how many UUIDs you need.
- Choose whether to uppercase them or remove hyphens.
- Click Generate UUIDs.
- Copy a single UUID or use Copy All to grab the whole batch.
Frequently Asked Questions
What's the difference between a UUID and a GUID?
They're the same 128-bit identifier standard under two names. GUID is Microsoft's term from the Windows and.NET world, while UUID is the name used everywhere else, including Linux, Python, and PostgreSQL. In everyday use they're interchangeable.
Is a UUID v4 guaranteed to be unique?
Not literally guaranteed, but the odds of a collision are effectively zero. With 122 random bits, you would need to generate billions of UUIDs every second for decades before a collision became likely.
Should I use UUID v4 as a database primary key?
It works, but fully random v4 values can fragment database indexes since they insert in no particular order. For high-volume tables, many teams now use UUID v7 instead, which stays globally unique but sorts by creation time.
What is a UUID used for?
UUIDs are commonly used as unique identifiers for database records, API resources, and distributed systems where IDs need to be generated without a central counter.
Can I remove the hyphens?
Yes, toggle off "Include hyphens" to get a 32-character compact form.
Does this tool log the UUIDs I generate?
No, everything is generated locally in your browser and nothing is sent to a server.
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