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.
Our professional solution for holding verified drawings with up to 10 million entries.
Simple verified giveaway service suitable for video streaming with up to 10,000 entries.
Randomize items of your own choosing, such as people's names.
Perhaps the Internet's most popular with 326 lotteries.
Draw cards from multiple shuffled decks of cards.
Toss coins to get heads or tails in many currencies.
Roll 6-sided dice using true randomness.
Generate integers in configurable ranges.
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.
Longer case studies about services we have provided to small and large customers.
Random values in the [0,1] range with configurable decimal places.
Random numbers to fit a normal distribution of your specification.
Randomize an integer sequence of your choice.
Generate multiple sets of non-repeating integers.
Create files with up to 20 million random values to your specification, e.g., promotional codes for printing or numbers for scientific simulation.
A large number of files with true random data in a raw format, generated daily by RANDOM.ORG since 2006. Programming skills required.
The popular game played in many countries.
Generate birdie holes for golf courses.
Generate alphanumeric strings with many options.
Make strong passwords for your Wi-Fi, etc.
Generate alternative versions of Lessness using the same rules as the famous author.
Randomize cut-ups from his letters.
Pick random times of the day with intervals down to one minute.
Pick random days across nearly 3,500 years.
Generate simple random bitmaps in black and white.
Pick random colors for example for use as web colors.
Pure white noise for composition or to test your audio equipment.
Random scales to help students of jazz guitar practice improvisation.
Our Basic and Signed APIs can be used to get true random numbers into your web app or mobile app.
Gives you all the features of the Third-Party Draw Service in a few handy methods.
Put a mini-RANDOM.ORG on your web page.
Put the result of a Third-Party Drawing on your web page.
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.
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.
These graphs show how the generator is performing right now.
Explains how you test random numbers for randomness.
Shows how much randomness RANDOM.ORG has generated since 1998.
Shows how many random bits you have left today and lets you buy more.