Random Number Generator · Practical guide
Random Number Generator 1 to 100
Each whole number from 1 to 100 has an equal 1% chance on every draw — set Min to 1 and Max to 100 above.
At a glance
Quick answer
To pick a random number from 1 to 100, set Min to 1 and Max to 100 above — every integer in that range has an exactly equal 1% chance of coming up on each draw. Raise the Count to generate up to 100 numbers in a single run, and uncheck Allow Duplicates if every result must be unique.
Interactive tool
Random Number Generator
Enter your own values, then compare the result with the examples below.
Generated Numbers
History (last 5)
How the Odds Work
With 100 equally likely outcomes, the probability of any specific number on one draw is 1/100 = 1%. The long-run average of many draws lands at the midpoint of the range, (1 + 100) / 2 = 50.5, and the most common result is a tie — all 100 values share it.
Chance a Specific Number Appears in Multiple Draws
Drawing with replacement (duplicates allowed), the probability that one chosen number appears at least once grows with each draw:
| Draws | Chance your number appears |
|---|---|
| 1 | 1.00% |
| 5 | 4.90% |
| 10 | 9.56% |
| 25 | 22.22% |
| 50 | 39.50% |
Common Uses for 1–100
A 1-to-100 range doubles as a percentage roll in tabletop games (a roll of 20 or under succeeds at a 20% chance), a random percentile for classroom sampling, or a fair way to pick one entry out of 100 raffle tickets. For unique picks — say, 5 different winners from tickets 1 to 100 — set Count to 5 and turn duplicates off; the range is more than large enough to support it.
Decimals in the Same Range
Switch the type to Decimal and the generator produces values anywhere in [1, 100), rounded to six decimal places — useful for random percentages like 73.4812 or simulated measurements. The midpoint of the distribution stays at 50.5 either way.
Frequently Asked Questions
Is every number from 1 to 100 equally likely?
Yes. The generator picks integers uniformly across the range, so 1, 50, and 100 each carry the same 1% probability per draw.
Can I get the same number twice in one run?
Only if Allow Duplicates is checked. Uncheck it and every number in a run is unique — the range just needs at least as many values as the count you request.
How random are the results?
The tool uses JavaScript's Math.random(), a pseudo-random algorithm that is statistically fine for games, raffles, and sampling, but not designed for cryptography.
What is the average of numbers from 1 to 100?
The expected value is the midpoint, (1 + 100) / 2 = 50.5. Over many draws, your results will cluster around that figure.