UUID Generator
Generate cryptographically random version 4 UUIDs in bulk, then copy or download them.
How to use the UUID Generator
- Enter how many UUIDs you need (1 to 1,000).
- Choose uppercase and whether to include hyphens, then press Generate.
- Copy a single UUID with its own Copy button, or use “Copy all” for a newline-separated list.
- Press “Download .txt” to save the list as a text file with one UUID per line.
Good to know
- Generates version 4 (random) UUIDs. 122 of the 128 bits are random; the remaining bits mark the version and RFC 4122 variant.
- Randomness comes from crypto.randomUUID() or crypto.getRandomValues(). If neither exists, the tool shows an error instead of falling back to a weaker generator such as Math.random().
- UUIDs are identifiers, not secrets. They are unguessable in practice, but do not use one as a password or API key.
- Nothing is stored or sent anywhere; the list disappears when you leave or reset the page.
Examples
- Standard format
- 3f2b8c1e-9a4d-4e7b-8c21-5d6f0a1b2c3d 8-4-4-4-12 hexadecimal digits; the first digit of the third group is always 4.
- Compact format
- Without hyphens: 3f2b8c1e9a4d4e7b8c215d6f0a1b2c3d (32 characters), common for database keys and file names.
- Bulk test data
- Generate 100, press “Copy all” and paste the list into a spreadsheet or a seed script.
Frequently asked questions
Can two generated UUIDs be the same?
It is possible in theory but vanishingly unlikely: with 122 random bits you would need to generate billions of UUIDs per second for decades before a collision became probable.
What is the difference between a UUID and a GUID?
GUID is Microsoft's name for the same 128-bit identifier format. A version 4 UUID is valid wherever a GUID is expected.
Why is the quantity limited to 1,000?
A cap keeps the page responsive and the list readable. You can generate another batch as often as you like.
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