Version 4 (random)
The most common UUID — 122 random bits from the browser’s cryptographic generator. Suitable for almost anything.
UUID / GUID Generator
Generate UUID version 4 (random), version 7 (time-ordered) and NIL — one at a time or in bulk, in the format you need. Everything runs in your browser.
Version 7 (time-ordered)
Starts with a timestamp so it sorts chronologically — better for database primary keys.
Your format
Toggle uppercase, braces { } (Microsoft GUID style) and hyphens, and generate up to 100 at once.
Frequently asked questions
What is a UUID (GUID)?
A UUID (Universally Unique Identifier), also called a GUID, is a 128-bit identifier written as 32 hexadecimal characters in five groups (8-4-4-4-12). It is designed to be unique without a central registry, which is why it is used for database keys, object identifiers, files and request IDs.
What is the difference between version 4 and version 7?
Version 4 is fully random — the most common kind, ideal for general identifiers. Version 7 starts with a 48-bit timestamp (Unix milliseconds) followed by random bits, so the UUIDs sort by creation time. That makes v7 better for database primary keys (improved index locality).
What is a NIL UUID?
The NIL UUID is the special all-zero value (00000000-0000-0000-0000-000000000000). It is used as an "empty" or placeholder identifier when you need to represent the absence of a value.
Are the generated UUIDs random and secure?
Yes. Version 4 and the random portion of version 7 use crypto.getRandomValues — the browser’s cryptographically secure random number generator. The chance of a v4 collision is negligibly small.
Can I generate several at once?
Yes. Set a count (up to 100) and press "Generate" to get a list. You can copy each one individually or all at once, and use the uppercase, braces { } (GUID style) and hyphen options to match the exact format you need.
Is my data uploaded anywhere?
No. UUIDs are generated entirely locally in your browser via JavaScript — nothing is sent to a server.