UUID Generator
runs in your browserno sign-upfree
Generate random v4 or time-ordered v7 UUIDs (GUIDs) — one or hundreds at once.
About this tool
A UUID (also called a GUID) is a 128-bit identifier that is practically guaranteed to be unique — ideal for database keys, file names, request IDs and test data. This generator creates random version 4 UUIDs or time-ordered version 7 UUIDs using your browser’s secure random number generator, one at a time or in bulk.
How to use
- Choose the version: v4 (random) or v7 (time-ordered).
- Set how many you need and the format: uppercase, with or without hyphens, or in { braces }.
- Copy the UUIDs or download them as a text file. Press Generate for a new batch.
FAQ
Should I use UUID v4 or v7?
v4 is fully random and the most widely supported. v7 (RFC 9562) starts with a timestamp, so new IDs sort after older ones — this keeps database indexes efficient. Use v7 for database primary keys if your system supports it; otherwise v4.
Can two generated UUIDs be the same?
In practice, no. A v4 UUID has 122 random bits; you would need to generate billions of UUIDs every second for many years before a duplicate became likely.
What is the difference between a UUID and a GUID?
They are the same thing. GUID is Microsoft’s name for a UUID, often written in uppercase inside { braces }.
Are the UUIDs generated securely?
Yes. They are created in your browser with the Web Crypto API (crypto.randomUUID and crypto.getRandomValues). Nothing is sent to a server.