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True Random Integer Generator


True Random Dice Roller


True Random Card Shuffler


What's the fuss about true randomness?

Perhaps you have wondered how predictable machines like computers can generate randomness. In reality, most random numbers used in computer programs are pseudo-random, which means they are generated in a predictable fashion using a mathematical formula. This is fine for many purposes, but it may not be random in the way you expect if you're used to dice rolls and lottery drawings.

RANDOM.ORG produces true random numbers from atmospheric noise, which for many purposes are better than pseudo-random numbers. People use RANDOM.ORG for a myriad of things, including holding drawings, lotteries and sweepstakes, to drive online games, for scientific applications, and for art and music. The service has existed since 1998 and was built by Dr Mads Haahr of the School of Computer Science and Statistics at Trinity College, Dublin in Ireland. Today, RANDOM.ORG is operated by Randomness and Integrity Services Ltd.

Popular Randomizers

Third-Party Drawings

Our professional solution for holding verified drawings with up to 10 million entries.

Multi-Round Giveaways

Simple verified giveaway service suitable for video streaming with up to 10,000 entries.

List Randomizer

Randomize items of your own choosing, such as people's names.

Lottery Quick Pick

Perhaps the Internet's most popular with 326 lotteries.

Playing Card Shuffler

Draw cards from multiple shuffled decks of cards.

Coin Flipper

Toss coins to get heads or tails in many currencies.

Dice Roller

Roll 6-sided dice using true randomness.

Random Integers

Generate integers in configurable ranges.

Customers and Community

Our Customers

Companies and brands you may know who we're proud to count amongst our clients.


Get inspired by how people are using our services for all sorts incredible things.

Use Cases

Longer case studies about services we have provided to small and large customers.

Numbers, etc.

Decimal Fractions

Random values in the [0,1] range with configurable decimal places.

Gaussian Numbers

Random numbers to fit a normal distribution of your specification.

Sequence Randomizer

Randomize an integer sequence of your choice.

Integer Sets

Generate multiple sets of non-repeating integers.

Generate Large Files

Create files with up to 20 million random values to your specification, e.g., promotional codes for printing or numbers for scientific simulation.

File Archive

A large number of files with true random data in a raw format, generated daily by RANDOM.ORG since 2006. Programming skills required.

Games and Lotteries

Keno Quick Pick

The popular game played in many countries.

Birdie Funds

Generate birdie holes for golf courses.

Strings and Text

String Generator

Generate alphanumeric strings with many options.

Password Generator

Make strong passwords for your Wi-Fi, etc.

Samuel Beckett

Generate alternative versions of Lessness using the same rules as the famous author.

William S. Burroughs

Randomize cut-ups of manuscript pages of his published work, creating new words and altered meanings.

Time and Space

Clock Times

Pick random times of the day with intervals down to one minute.

Calendar Dates

Pick random days across nearly 3,500 years.

Geographic Coordinates

Pick random spots on our planet's surface.

Color and Sound


Generate simple random bitmaps in black and white.

Hex Color Codes

Pick random colors for example for use as web colors.

Audio Noise

Pure white noise for composition or to test your audio equipment.

Jazz Scales

Random scales to help students of jazz guitar practice improvisation.

APIs and Technical Docs

Core API

Our Basic and Signed APIs can be used to get true random numbers into your web app or mobile app.

Draw Service API

Gives you all the features of the Third-Party Draw Service in a few handy methods.

Widgets for Your Site

Integer Widget

Put a mini-RANDOM.ORG on your web page.

Draw Widget

Put the result of a Third-Party Drawing on your web page.

Learn about Randomness


Explains what true random numbers are and why they are interesting.


The story of how RANDOM.ORG started in 1997 and where it is today.


From folks have found very creative uses for true random numbers.


Thanks to all the generous folks who have helped out over the years.


Our small collection of quotes about randomness in science, the arts and life.

Media and Science

Inexhaustive list of popular print mentions and scientific citations of RANDOM.ORG.


Our FAQ contains answers to common questions about the service and how to use it.


Appears at highly random intervals, but do sign up.


Real-Time Statistics

These graphs show how the generator is performing right now.

Statistical Analysis

Explains how you test random numbers for randomness.

Bit Tally

Shows how much randomness RANDOM.ORG has generated since 1998.

Your Quota

Shows how many random bits you have left today and lets you buy more.