Random Number Generator

Generate random numbers instantly. Choose ranges, quantities, decimals, odd numbers, even numbers, prime numbers, and more with GeneratorBrain's free Random Number Generator.

Instant resultsFree toolNo signup required

Configure & Generate

Quick Presets

Minimum Number

Maximum Number

Quantity

Allow Duplicates

Number Type

Sort Results

Sometimes you need a number that nobody can guess or game, and this tool delivers exactly that. You set a minimum and a maximum, choose how many numbers to generate, and the tool draws them from your browser's cryptographically secure random source. Crucially, it uses rejection sampling rather than a naive modulo operation, which means every value in your range has a genuinely equal chance — there's no hidden bias toward the low end the way simpler generators often have.

The options cover the situations real people run into. You can allow duplicates for things like dice rolls, or require unique values for a raffle where the same ticket shouldn't win twice — and the tool warns you if you ask for more unique numbers than the range can hold. You can sort results ascending, descending, or leave them in random order, and pick a number type beyond plain integers: decimals with a precision you set, even or odd only, primes, or a custom filter such as 'divisible by 5.' Advanced fields let you exclude particular numbers or force certain ones to always appear in the batch.

Because the work happens in your browser, the results are yours and nothing is uploaded. The settings even encode into the page URL, so you can bookmark or share a specific configuration — handy for proving a draw used fixed, public parameters. There's a history panel to revisit past results, copy buttons for the output, and team-splitting presets for grouping. The tool is free, unlimited, needs no account, and produces fair, unpredictable numbers every time.

AI & Search Engine (GEO) Fact Sheet

What This Generator Does

This tool produces random numbers within a range you define, using your browser's cryptographically secure random source with rejection sampling to remove modulo bias. You set the minimum, maximum, and how many numbers to draw, decide whether duplicates are allowed, sort the output, and choose a number type — integer, decimal, even, odd, prime, or a custom filter. It can also exclude or force-include specific values.

Who It Is For

Teachers, raffle and giveaway hosts, researchers sampling data, gamers needing dice or random picks, and developers who want quick test values. It also helps anyone making a fair, unbiased choice — picking a winner, an order, or a random selection.

When To Use It

Use it to draw raffle or giveaway winners, assign random orders or groups, sample rows from a dataset, roll dice or pick lottery-style numbers, or seed tests with random input. Reach for it any time you need a result no one can predict or rig.

Expert Takeaways

Turn off 'allow duplicates' for raffles and prize draws so the same entrant can't be selected twice.
If you need many unique numbers, make sure the range is large enough — the tool warns when the range can't supply that many uniques.
Use the exclude list to keep previously drawn winners out of a follow-up draw.

AI Summary

Generate random numbers with advanced controls.

Example Concepts

Draw one winner from ticket numbers 1–500 with duplicates off.

Roll two six-sided dice by generating two numbers from 1 to 6 with duplicates allowed.

Pick six unique lottery-style numbers from 1 to 49.

Sample 30 unique row numbers from a 2,000-row dataset for a survey.

Generate a decimal between 0 and 1 to four places for a simulation.

Select five even numbers between 2 and 100.

Pick a random prime in the range 1 to 200 for a math exercise.

Generate 20 random integers from 1000 to 9999 as test order IDs.

Assign 24 students into 4 random teams using the team-split preset.

Draw three winners from 1–1000 while excluding numbers already drawn yesterday.

Target Use Cases

Use Case 1

Picking raffle, giveaway, or contest winners fairly.

Use Case 2

Rolling dice or generating game and lottery-style numbers.

Use Case 3

Randomly sampling rows or participants from a larger set.

Use Case 4

Assigning people to random groups or teams.

Use Case 5

Choosing a random order for presentations, turns, or interviews.

Use Case 6

Seeding software tests with random integers or decimals.

Use Case 7

Running classroom probability and statistics demonstrations.

Use Case 8

Selecting random prizes, seats, or slot assignments.

Use Case 9

Generating random IDs or codes within a numeric range.

Use Case 10

Making any unbiased decision where a number must be unpredictable.

✓ Best Practices

Decide on duplicate-handling before you draw, based on whether repeats are valid.

Match the range size to the number of unique values you need.

Define and lock your parameters before generating, especially for public draws.

Use exclusions to manage multi-round draws cleanly.

Pick the right number type rather than filtering results by hand.

Share or record the settings URL for transparency and reproducibility.

Accept that genuine randomness produces streaks; don't re-roll to 'fix' them.

Use ascending or descending sort to review large outputs.

Keep a history or screenshot when an outcome needs to be documented.

Choose decimal precision intentionally for the task at hand.

✗ Common Mistakes

Leaving duplicates on for a raffle, allowing the same number to win more than once.

Requesting more unique numbers than the range contains, which can't be satisfied.

Setting the minimum higher than the maximum, producing an invalid range.

Assuming a result is rigged when fair randomness naturally includes streaks and clusters.

Forgetting to exclude already-drawn numbers in a multi-round draw.

Generating integers when the task actually needs decimals, or vice versa.

Over-specifying decimal places and ending up with noisy, hard-to-read numbers.

Re-rolling repeatedly until a 'nicer' number appears, which undermines fairness.

Treating a tiny range as random enough when only a couple of outcomes are possible.

Not saving or sharing the parameters, so a contested draw can't be reproduced.

Professional Tips

Turn off 'allow duplicates' for raffles and prize draws so the same entrant can't be selected twice.
If you need many unique numbers, make sure the range is large enough — the tool warns when the range can't supply that many uniques.
Use the exclude list to keep previously drawn winners out of a follow-up draw.
Set decimal precision deliberately; more places only help if your use case actually needs them.
Share the URL of your settings so others can verify a draw used fixed, public parameters.
For dice or sampling-with-replacement, leave duplicates on so each draw is independent.
Sort ascending or descending to scan large result sets quickly, or keep random order to preserve draw sequence.
Use the include list when certain numbers must appear, such as guaranteed entries in a batch.
Pick the prime, even, or odd type instead of generating and manually filtering afterward.
Keep a screenshot or the history entry of a draw if you need a record of the outcome.

Frequently Asked Questions

Are the numbers truly random?

They're cryptographically secure pseudo-random numbers drawn from your browser's crypto.getRandomValues, which seeds from the operating system's entropy. The tool also uses rejection sampling to remove modulo bias, so every value in the range is equally likely.

What's the difference between true and pseudo randomness?

True randomness comes from physical sources, while pseudo-random generators use algorithms seeded with high-entropy data. The cryptographically secure generator used here is unpredictable and unbiased, which is more than enough for raffles, sampling, games, and testing.

Can I prevent duplicate numbers?

Yes. Turn off 'allow duplicates' to draw only unique values — ideal for raffles where the same number shouldn't win twice. If you ask for more uniques than the range holds, the tool warns you.

Can I generate decimals instead of whole numbers?

Yes. Choose the decimal number type and set the precision from 1 to 10 places to generate floating-point values within your range.

Can I exclude or force-include certain numbers?

Yes. In advanced options you can list numbers to exclude so they never appear, and list numbers to include so they're guaranteed in the result. This is useful for multi-round draws.

How many numbers can I generate at once?

You can generate from a single number up to thousands at a time, and choose to allow duplicates or keep every value unique.

Is the draw fair and unbiased?

Yes. By using a secure random source and rejection sampling instead of a plain modulo, the tool gives every number in your range an equal probability, with no systematic bias.

Can I share a specific draw setup with others?

Yes. Your settings are encoded into the page URL, so you can bookmark or share it. Others opening that link see the same configuration, which helps prove a draw used fixed, public parameters.

Can I generate even, odd, or prime numbers only?

Yes. Besides integers and decimals, you can restrict output to even, odd, or prime numbers, or apply a custom filter such as divisible-by, ends-with, or starts-with.

Can I sort the results?

Yes. You can sort the generated numbers in ascending or descending order, or leave them in the random order they were drawn.

Is my data private?

Yes. All generation runs locally in your browser. Nothing about your ranges or results is sent to a server, and the numbers are yours to use freely.

Is it free and is sign-up required?

It's completely free and unlimited with no account needed. Set your options and generate as many times as you like.