UUID Generator Online
Generate random UUID v4 values instantly — one or a hundred at a time, entirely in your browser.
Never uploaded
UUIDs are generated entirely in your browser using its built-in secure random number generator.
UUID v4, up to 100 at once
Cryptographically random, with hyphen and case options to match whatever format you need.
Free, no limit
No account, and no limit on how many UUIDs you can generate.
What is a UUID?
A UUID (Universally Unique Identifier) is a 128-bit value, usually written as 32 hexadecimal digits in five hyphen-separated groups (like 123e4567-e89b-12d3-a456-426614174000), used to identify something — a database row, a session, a file, a device — without needing a central authority to hand out IDs. The chance of two randomly generated UUIDs colliding is astronomically small, making them safe to generate independently across any number of systems.
How to Generate a UUID Online
- Set your options. Choose how many UUIDs you need (up to 100), whether to include hyphens, and lowercase or uppercase hex digits.
- Generate. A UUID is created automatically when the page loads — click "Generate new" for a fresh batch anytime.
- Copy or download. Use "Copy all" to copy every UUID to your clipboard, or "Download .txt" to save them as a file, one per line.
UUID v4: Random, Not Sequential
This tool generates version 4 UUIDs — the random variant, and by far the most commonly used in practice. A v4 UUID is built from 122 random bits (the remaining 6 bits are fixed to mark the version and variant per the UUID specification), generated using your browser's cryptographically secure random number generator (crypto.randomUUID()). Unlike sequential IDs, v4 UUIDs reveal nothing about when or in what order they were created.
Frequently Asked Questions
How do I generate a UUID?
A random UUID (version 4) is generated automatically when the page loads — click "Generate new" for another one, or set a quantity to generate several at once.
What is a UUID?
A UUID (Universally Unique Identifier) is a 128-bit value, usually written as 32 hexadecimal digits in five groups, used to identify something without a central authority handing out IDs.
What UUID version does this generate?
Version 4 — the random variant, and by far the most commonly used in practice, generated using your browser's cryptographically secure random number generator.
Can I generate multiple UUIDs at once?
Yes — choose how many to generate (up to 100 at a time) and they all appear in the list together, ready to copy or download as one file.
Can I generate a UUID without hyphens or in uppercase?
Yes — toggle "Hyphens" off for a plain 32-character string, and toggle "Uppercase" on if your system expects capital hex digits instead of lowercase.
Are these UUIDs guaranteed to be unique?
Not mathematically guaranteed, but the collision probability is astronomically low — practically impossible to hit by chance.
Is my data uploaded anywhere?
No. UUIDs are generated entirely in your browser using its built-in secure random number generator — nothing is sent to CurePDF's servers.
Is the UUID generator free?
Yes, with no account required and no limit on how many UUIDs you can generate.