UUID & Token Generator
Generate v4 UUIDs in bulk and secure random tokens with custom length and character sets.
Generated token appears here.About the UUID & Token Generator
This tool generates version 4 UUIDs and secure random tokens directly in your browser using the Web Crypto API, the same cryptographically strong random source used for keys and session identifiers. Nothing is generated on a server, which means no one else ever sees the values, and there is no rate limit.
A v4 UUID is a 128 bit identifier with 122 bits of randomness, formatted as five groups of hexadecimal characters. The chance of two independently generated v4 UUIDs colliding is so small that systems all over the world treat them as unique without coordination. Use them as database keys, request identifiers, file names, or anywhere you need an identifier that no other system will accidentally produce.
The token generator produces random strings for API keys, temporary passwords, webhook secrets, and similar uses. You control the length and which character sets are included. Tokens are generated with rejection sampling, so every character in your chosen set has an equal chance of appearing; there is no modulo bias weakening the result.
For passwords, longer is better than more complex. A 24 character token from letters and digits is far stronger than an 8 character token with symbols. If a site limits symbols, increase the length instead.
Reach developers and designers who use these tools every day. Privacy-first, no trackers.
Frequently asked questions
Are these UUIDs really unique?
A v4 UUID contains 122 random bits, which gives about 5.3 undecillion possible values, and this tool draws them from crypto.getRandomValues, the cryptographically secure random source in your browser. Uniqueness is probabilistic rather than coordinated: no central registry exists, and two machines generating UUIDs independently rely purely on the odds of collision being absurd. The odds are, in fact, absurd. Generating a billion UUIDs per second continuously for around 85 years gives roughly a 50 percent chance of a single duplicate, and any realistic system sits so far below that scale that collisions are not a practical engineering concern. When real world duplicates do occur, the cause is essentially never probability: it is a broken random source, a virtual machine cloned with its state, or code accidentally reusing a stored value. Use v4 UUIDs freely as identifiers; treat an observed collision as a bug to investigate, not bad luck.
Are the tokens safe to use as passwords or API keys?
Yes. Tokens are generated with crypto.getRandomValues, the cryptographically secure random source in your browser, with rejection sampling to keep every character equally likely. They are generated locally and never transmitted, logged, or stored.
What is the difference between UUID v4 and other versions?
v4 is purely random: 122 bits of randomness with 6 bits fixed for version and variant markers. The other versions encode meaning into the value. v1 and its reordered successor v6 embed a timestamp and originally a MAC address, which made them sortable but leaked when and where they were generated. v5 is deterministic: it hashes a namespace and a name, so the same inputs always yield the same UUID, useful for stable identifiers derived from external keys. v7, the newest, puts a millisecond timestamp in the high bits followed by randomness, so values sort by creation time, which makes database indexes noticeably happier than v4 under heavy insert load. The practical guidance: v4 is the right default when you simply need a unique identifier, v7 is worth choosing for high volume database primary keys, and v5 fits when identity must be derivable rather than random.
Can I generate UUIDs in bulk?
Yes, up to 100 at a time. Each one can be copied individually, or use the copy button at the top of the panel to copy the whole list with one UUID per line.
Does this tool store or send the generated values anywhere?
No. Generation happens in your browser with the Web Crypto API. The values exist only on your screen and in your clipboard after you copy them.