Version 4 UUIDs are generated randomly, so the chance of a collision is negligible for practical purposes: you would need to generate about a billion UUIDs per second for a century to reach a fifty percent chance of a single duplicate. Generation uses the browser cryptographic random API where available and never leaves your device.
Calculator
How to use the UUID Generator
- Choose how many UUIDs you need.
- Pick the output format your system expects.
- Press Calculate to generate a fresh batch.
- Copy the list straight into your code or database seed.
About this tool
The UUID Generator is built for speed and accuracy: every calculation runs in your browser, so your data never leaves your device and the result updates as you type. It works equally well on a phone, a tablet or a desktop, and it is free to use as many times as you like.
Common use cases
- Generating primary keys for a new database table.
- Creating correlation IDs for API requests.
- Seeding test fixtures with unique identifiers.
- Producing unique filenames or session tokens.
Tips for the best result
- Use the latest figures you have - even a small change in rate or term can shift the outcome by hundreds.
- For annual figures, divide by 12 to get a monthly number you can compare with the result.
- Bookmark this page and revisit the calculation as the inputs change.
Frequently asked questions
What version of UUID is this?
Version 4, which is built from random numbers. The version nibble is set to 4 and the variant bits follow RFC 4122, so the output is standards compliant.
Can two UUIDs collide?
Theoretically yes, practically no. With 122 random bits the probability is so small that random v4 UUIDs are treated as unique everywhere.
Related tools you may like
Syllable Counter For English TextText · English syllable counting is famously irregular - "fire" is one syllable, "hour" is one, "…Vowel CounterText · The Vowel Counter tells you how many vowels are in a passage, which ones dominate, and wha…Random Sentence GeneratorText · The Random Sentence Generator builds complete English sentences from a vocabulary of subje…Word CounterText · The Word Counter analyses whatever you paste and updates every statistic as you type: tota…Text To ASCII ConverterText · The Text To ASCII Converter translates in both directions. Enter normal text and receive t…Random Word GeneratorText · The Random Word Generator produces random English words on demand. Choose how many you nee…Inches to Cm ConverterConverters · This Inches to Cm Converter handles imperial to metric length in both directions. Enter in…Time Duration CalculatorDate · The Time Duration Calculator measures how much time passes between two timestamps. Enter a…