UUID Generator
Generate random UUID / GUID v4 identifiers online, in bulk. Free developer tool.
Free · No sign-upHow to use UUID Generator
- 1. Enter how many identifiers you need in the Count box, anywhere from 1 to 100 per batch.
- 2. Click Generate to create a fresh list of random version 4 UUIDs, one per line, in the output box.
- 3. Click Copy to put the whole list on your clipboard, ready to paste into code, a database seed file or a spreadsheet.
- 4. Click Generate again whenever you need new values; each batch is created from scratch, so earlier IDs are never reused.
Frequently asked questions
Is the UUID generator free, and how many UUIDs can I make at once?
Yes, it’s free with no sign-up. Each click generates up to 1,000 UUIDs (version 4 random or version 7 time-ordered), one per line, and you can copy them or download a .txt file and click Generate as often as you like.
Are the UUIDs generated privately in my browser?
Yes. UUIDs are created in your browser with the built-in crypto.randomUUID and crypto.getRandomValues functions, which use a cryptographically secure random source. Nothing is sent to or stored on our server, so the values are known only to you.
What is a version 4 UUID?
A UUID v4 is a 128-bit identifier written as 32 hex digits in five groups, like xxxxxxxx-xxxx-4xxx-yxxx-xxxxxxxxxxxx. Apart from a few fixed version and variant bits, it’s random, which makes it handy as a database key or request ID without a central counter.
Can two randomly generated UUIDs ever be the same?
In theory yes, but a version 4 UUID has 122 random bits, so the chance of a duplicate is astronomically small for any realistic number of IDs. For most apps you can treat them as unique, though a unique constraint in your database is still good practice.
How do I generate a UUID for a database primary key?
Set Count to the number of rows you need, click Generate, then Copy and paste the values into your insert script or seed file. Most databases, including PostgreSQL, MySQL and SQL Server, accept this standard 36-character hyphenated format.
What format are the generated UUIDs in, and does it work in all browsers?
By default each UUID is lowercase, 36 characters with hyphens, one per line (RFC 9562, formerly RFC 4122). It relies on crypto.randomUUID (or crypto.getRandomValues where that is missing), available in every current browser. You can switch to UPPERCASE, remove the hyphens or add {braces} for .NET-style GUIDs.