Is this random number generator truly random?

This generator uses JavaScript's Math.random() function, which is a pseudorandom number generator (PRNG). It produces numbers that appear random and are statistically uniform, but are generated by a deterministic algorithm seeded from system entropy. For most purposes — games, simulations, picking raffle winners, generating test data — this is perfectly suitable. The output is unpredictable in practice. For cryptographic security (passwords, encryption keys, security tokens), use a cryptographically secure random number generator (CSPRNG) such as the Web Crypto API's crypto.getRandomValues(), which sources entropy from the operating system. For physical randomness (true RNG), hardware devices sample physical processes like radioactive decay or thermal noise. Services like random.org use atmospheric noise.

How do I generate random numbers without repeats?

Use the Multiple mode with the No repeats checkbox enabled. This uses the Fisher-Yates shuffle algorithm internally: 1. Create a pool of all integers from min to max 2. Randomly pick one from the pool and remove it 3. Repeat until you have the required count 4. Sort the results Example: pick 6 unique numbers from 1-49 (lottery): - Pool starts as [1, 2, 3, ..., 49] - Random index picked, number removed - Repeated 6 times - Result: 6 unique numbers, sorted ascending Constraint: the count cannot exceed the range size. If you want 10 unique numbers from 1-5, that is impossible (only 5 exist in the range). The Lottery mode also uses no-repeat generation automatically.

How do dice probabilities work?

For a single fair die with n sides, each outcome (1 to n) has probability 1/n. For multiple dice, the sum follows a bell-curve distribution — middle values are more likely than extremes. For 2d6 (two standard dice, sums 2-12): - Most likely: 7 (6 ways: 1+6, 2+5, 3+4, 4+3, 5+2, 6+1) = 6/36 = 16.7% - Least likely: 2 and 12 (1 way each) = 1/36 = 2.8% Average roll: - 1d6: average = 3.5 - 2d6: average = 7 - 1d20: average = 10.5 - nd[s]: average = n × (s+1)/2 This is why RPG combat feels more consistent with 2d6 than 1d12 — even though both have the same range (2-12 vs 1-12), the 2d6 distribution clusters near 7 while 1d12 is flat.

What are the odds of winning a lottery?

Lottery odds depend on the number of combinations. For picking k numbers from a pool of n: Odds = 1 in C(n,k) = n! / (k! × (n-k)!) Common lotteries: - UK Lotto (6 from 59): 1 in 45,057,474 - Powerball (5 from 69): 1 in 11,238,513 (jackpot adds a Powerball) - EuroMillions (5 from 50): 1 in 2,118,760 (jackpot adds star balls) - 6/49: 1 in 13,983,816 For context: - Being struck by lightning in a year: ~1 in 1,222,000 - Flipping 20 heads in a row: 1 in 1,048,576 This random number generator picks numbers with equal probability — it cannot improve your lottery odds. Every combination has exactly the same probability of winning.

Can I use this for a raffle or giveaway?

Yes — this generator is suitable for informal raffles and giveaways. For fairness: 1. Assign each participant a number (1, 2, 3...) 2. Set the range to match your participant count 3. Click Generate to pick the winner 4. Screenshot or record the result for transparency For multiple winners without repeats: 1. Use Multiple mode 2. Enable No repeats 3. Set count = number of prizes 4. Generate once to get all winner numbers simultaneously For professional or high-stakes draws (company promotions, legal compliance), consider a certified random number service with audit trails, such as random.org or a third-party draw service that provides verifiable proof of randomness. For everyday classroom draws, game nights, and informal competitions, this generator is perfectly appropriate.

Random Number Generator — Single, Multiple, Dice, Coin & Lottery

The Random Number Generator has five modes in one tool. Single: generate one random integer between any min and max. Multiple: generate several numbers at once with optional no-repeat mode for raffles and draws. Dice: roll any combination of dice — d4, d6, d8, d10, d12, d20, d100 — with sum and stat...

GENERATOR

Min

Max

Range: 1 to 100 (100 possible values)

HISTORY & STATS

Generate numbers to see history

🎲

Dice Roller

Roll any number of dice with any sides — d4, d6, d8, d10, d12, d20, d100

🪙

Coin Flipper

Fair 50/50 coin flip. Tracks heads/tails count across the session.

🎰

Lottery Picker

Pick unique numbers for lotteries — UK Lotto, Powerball, EuroMillions, or custom.

🔢

Custom Range

Generate one or many random numbers from any min-max range.

Created with❤️byeaglecalculator.com

HOW TO USE

1
Choose a mode: Single (one number in a range), Multiple (several numbers at once), Dice (roll any dice), Coin (flip a coin), or Lottery (pick unique numbers like a lottery draw).
2
Single mode: set your minimum and maximum values, then click Generate. The result appears as a large number. Click Regenerate to get a new number in the same range.
3
Multiple mode: set min, max, and how many numbers to generate. Enable No repeats to get unique numbers only — useful for draws, raffles, or selecting random items from a list.
4
Dice mode: choose how many dice and how many sides. Quick presets: 1d6 (standard die), 2d6 (board games), 1d20 (D&D). The sum of all dice is shown alongside individual rolls.
5
Lottery mode: set how many numbers to pick and the pool size. Quick presets for UK Lotto (6 from 59), Powerball (5 from 69), and EuroMillions (5 from 50). Numbers are always unique and sorted. History tracks your last 10 generations with coin and dice statistics.

WORKED EXAMPLE

Single: range 1-100, result = one random integer. Multiple: 6 unique numbers from 1-49 → lottery numbers (no repeats). Dice: 2d6 → two rolls each 1-6, sum shown. Average 2d6 = 7. Coin: 50% heads, 50% tails, independent each flip. UK Lotto: 6 from 59, odds = 1 in 45,057,474.

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Last updated: April 29, 2026 · Uses JavaScript Math.random() (PRNG) · Eagle-eyed accuracy for every calculation.