Random data generators, made in your browser
Passwords, UUIDs, numbers, test data, lists and colour palettes, made on your device with its cryptographic random source. Nothing is uploaded.
Table of generators
Thirty-four tools, grouped the way you reach for them.
Secrets
Identifiers
Numbers
Test data
- Fake data generatorBuild a schema, export JSON, CSV or SQL
- Fake name generatorRealistic names in six locales
- Random email generatorSafe test addresses on reserved domains
- Random address generatorUS addresses with ZIP codes, plus 6 countries
- Random phone number generatorFormatted numbers for forms and fixtures
- Random IP address generatorIPv4, IPv6, public or private ranges
- Random MAC address generatorUnicast, locally administered MACs
- Test credit card numbersLuhn-valid numbers for payment QA
- Random date generatorA random day between two dates, any format
- Random birthday generatorDates of birth for any age range
- Random year generatorYears in a range, leap-year filter
- Random month generatorA month, or all twelve shuffled
- Random day of the weekMonday to Sunday, or only days you pick
- Random time generatorA random time between two times
Lists & picks
Why a random data toolkit should run client-side
A password or API key generated on someone else’s server has already been seen by that server. RandomKit generates everything in the page itself using crypto.getRandomValues, the Web Crypto API defined by the W3C and implemented in every modern browser. You can load a tool, switch your connection off, and it keeps working.
The same approach makes bulk test data fast: ten thousand rows of names, emails and UUIDs are built in memory in a fraction of a second and exported as JSON, CSV or SQL inserts without a round trip.
Randomness done carelessly has subtle bugs. Math.random() is not designed for secrets, and the common rand() % n trick makes some results more likely than others. Our guide on how randomness works in software lets you see modulo bias happen, and explains the rejection sampling RandomKit uses to avoid it.
Questions people ask
Is the data really random?
Every generator on RandomKit draws from crypto.getRandomValues, the cryptographically secure random number generator built into your browser, which is seeded by your operating system. Integers are produced with rejection sampling so no value is more likely than another.
Does anything I generate leave my device?
No. Passwords, UUIDs, numbers, lists and test data are all generated by JavaScript running in your browser tab. The only features that contact a server are the optional AI helpers (describe a dataset or a palette mood), and they send only the short description you type, never generated values.
Can I use RandomKit output in production?
Passwords, API keys, UUIDs and Nano IDs are generated with the same CSPRNG that browsers use for TLS keys, so they are suitable for real use. Fake names, addresses and card numbers are for testing only: they are synthetic and must not be used to impersonate anyone or make purchases.
Is RandomKit free?
Yes. There are no accounts, limits or paid tiers. Bulk generators cap a single run at 10,000 rows to keep your browser responsive.