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Random Number Generator

Quick answer: This generator picks integers uniformly between your minimum and maximum, so every value in the range is equally likely. It uses a pseudorandom algorithm, which is fine for games, draws, sampling and shuffling. For cryptography, lotteries or security tokens, use a cryptographically secure generator or hardware randomness instead.

Last reviewed: September 2026

Generate numbers

Key facts

  • Random integer = floor(random × range) + min — every value in the range is equally likely.
  • A 1–100 draw gives each number exactly a 1% chance — including 100 itself.
  • Each draw is independent — past results never change the odds.
  • Browser randomness is fine for games and giveaways, not for passwords or cryptography.

A random number generator picks an unpredictable number inside a range you choose. This free tool generates random integers instantly — for raffles, dice rolls, sampling, shuffling, and everyday decisions.

Set the minimum, maximum, and how many numbers you want. Each result appears at once.

How to use

  1. Enter the minimum and maximum values.
  2. Choose how many numbers to generate.
  3. Press Calculate — your random numbers appear instantly.

Random integer formula

result = floor(random() × (max − min + 1)) + min
TermMeaning
random()A decimal from 0 (inclusive) to 1 (exclusive).
max − min + 1How many integers the range holds (the +1 includes both ends).
floor()Rounds down to a whole number.
+ minShifts the result up into your chosen range.

Example: min 1, max 100, random() = 0.4173 → floor(0.4173 × 100) + 1 = 41 + 1 = 42.

Worked examples

Raffle draw (1–100)

Range 1–100, one number: each integer has a 1/100 = 1% chance. A draw of 42 is exactly as likely as 1 or 100 — randomness has no favourites.

Dice roll (1–6)

Range 1–6, one number: each face has a 1/6 ≈ 16.7% chance. Rolling three times gives three independent results, e.g. 4, 2, 6 — the die has no memory of previous rolls.

Odds for common ranges

RangeValuesChance of any one valueTypical use
1–2250%Coin flip, yes/no
1–6616.7%Dice roll
1–101010%Quick picks
1–1001001%Raffles, percentages
1–100010000.1%Large draws, IDs

Every draw is independent, so each number keeps the same odds on every draw — like rolling a die again and again.

Frequently asked questions

Is it truly random?

It uses your browser’s pseudo-random generator — unpredictable enough for games, raffles, and sampling, but not for security. For passwords or tokens, use a cryptographic generator.

Can the same number appear twice?

Yes. Every draw is independent, so repeats are possible — in a 1–100 draw, the previous number repeats about 1% of the time.

Why did I get the same number twice in a row?

That is normal. In a 1–100 draw, back-to-back repeats happen about 1% of the time — randomness clusters more than intuition expects.

Is the maximum included?

Yes. Both ends of the range are included, and each value — min and max included — has identical odds.

Can I generate decimals?

This tool generates whole numbers. For a random decimal, generate an integer and divide — e.g. 1–1000 divided by 1000 gives 0.001–1.000.

Sources

  • Random.org — True random numbers and randomness explained
  • NIST — Randomness testing and standards

Key takeaways

  • Every value in the range is equally likely; both endpoints are included.
  • Draws are independent — past results never influence the next one.
  • Great for games and giveaways; use cryptographic randomness for anything security-related.

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