Random · Numbers
Random number 1 to 100.
A random number between 1 and 100, both included. Every number has exactly a 1% chance. Press Generate again for a new one, or ask for a batch.
Settings
Result
Press Generate.
A random number from 1 to 100
Pressing Generate picks one of 100 numbers with an equal 1 in 100 (1%) chance each. It uses your browser’s secure random generator, and the page draws a number as soon as it loads. Use How many for a batch; tick No repeats for a set of different numbers, and choose how to sort them.
Common uses for 1 to 100
- Percentages and chance events. Roll 1 to 100 for a “percentile” result: 1 to 25 is a 25% outcome, 1 to 60 a 60% one. Tabletop games often use two ten-sided dice this way.
- Raffles and classroom draws. Number your entries 1 to 100 and draw. For a list of names, use the name picker.
- Guessing games. “Higher or lower” from 1 to 100 is solvable in at most seven guesses by halving the range each time (27 = 128 is at least 100).
- Test data and sampling. Pick row numbers or IDs to spot-check.
How often does a batch repeat?
With repeats allowed, ten picks from 1 to 100 include at least one repeat about 37.2% of the time, and thirteen picks are the first batch size where a repeat is more likely than not (55.7%). That is the birthday problem with 100 possible values instead of 365. Tick No repeats if you need every number different.
Need a different range, decimals or negative numbers? Use the full random number generator. Smaller range: 1 to 10. Larger range: 1 to 1000.
Frequently asked questions
What is the chance of each number from 1 to 100?
Exactly 1 in 100, or 1%, for every number from 1 to 100 inclusive.
How do I get 10 different random numbers from 1 to 100?
Set How many to 10 and tick "No repeats". You can ask for up to 100 different numbers.
How likely is a repeat in 10 picks from 1 to 100?
With repeats allowed, ten picks contain at least one repeat about 37.2% of the time. Thirteen picks are the first where it is more likely than not (about 55.7%).
Can I use it as a percentile roll?
Yes. A number from 1 to 100 works as a percentile roll: any target of N% succeeds on N of the 100 numbers.
Is the number generated stored or tracked?
No. It is produced in your browser and is not sent anywhere. The history list lives in memory and clears when you reload.
Sources
Checked
Method notes: MDN describes crypto.getRandomValues() as returning cryptographically strong random values and says Math.random() does not provide cryptographically secure numbers. The W3C Web Cryptography API says the implementation, not the page, selects the seed. Range mapping uses rejection sampling and the Fisher-Yates shuffle, and both are unit-tested. Repeat-chance figures use the standard birthday-problem formula and are unit-tested. Everything runs in your browser. Nothing you enter or generate is sent anywhere or stored.
Scope
A general-purpose random tool for games, classrooms, sampling and everyday choices. It is not an audited lottery draw. For regulated contests, gaming or legal selections, follow the rules that apply to you.