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Random Number Generator

Generate random numbers within any range.

Processed on your device. We never see your files.

How to use Random Number Generator

What this tool does

The Random Number Generator draws whole numbers at random from a range you choose. You set a minimum and a maximum, decide how many numbers you want, and press Generate. The tool returns either a single large number or a tidy list of numbers, depending on how many you asked for. You can allow repeats or insist that every number is unique, and you can have the results sorted into ascending order for easier reading.

Under the hood it uses the browser’s Web Crypto API, the same source of randomness used for security-sensitive work. Crucially, it draws numbers in a way that avoids modulo bias — a subtle flaw where naive code makes some numbers slightly more likely than others. Every value in your range has an equal chance of being picked.

Use cases

A random number generator is one of those small tools that turns out to be useful constantly. Common uses include:

  • Raffles and giveaways — assign each entrant a number, then draw winners.
  • Sampling — pick random rows, records, or test cases from a numbered set.
  • Games and teaching — generate dice-like rolls, quiz answers, or practice arithmetic problems.
  • Decision-making — when two or more options are numbered, let chance choose.
  • Simulations — produce quick batches of random input for spreadsheets, scripts, or experiments.

Because it can generate up to 1000 numbers at once and copy them all in a single click, it also works as a fast way to seed a list you will paste elsewhere.

How to use it

  1. Enter the minimum and maximum of your range. Both ends are inclusive, so a range of 1 to 6 can return 1 or 6.
  2. Set how many numbers you want — anything from 1 to 1000.
  3. Decide whether to allow duplicates. With duplicates on, the same number can appear more than once. With them off, every number in the list is unique.
  4. Optionally tick sort results to have the list returned in ascending order.
  5. Press Generate. A single number is shown large and clear; multiple numbers appear as a list.
  6. Use Copy results to put the whole list on your clipboard, or Clear to start over.

If your inputs do not make sense — a minimum above the maximum, or more unique numbers than the range can supply — the tool shows a short message explaining how to fix it, and the Generate button stays disabled until the inputs are valid.

Privacy and your data

This generator runs entirely in your browser. No numbers, ranges, or settings are ever sent to a server, and nothing is stored between visits. When you refresh or close the page, the results are gone. There is no account, no tracking of what you generate, and no cloud sync. If you need a permanent record of a draw, copy the results and save them yourself.

Tips

For a fair draw, turn duplicates off so no entry can win twice. If you are sampling and want to allow the same item to be chosen again, leave duplicates on. When you generate a large batch, the sort option makes it much easier to scan for a specific value or to spot the spread of the results. Remember that both ends of the range are included: to draw a percentage from 0 to 100, set the minimum to 0 and the maximum to 100, which gives 101 possible values. If you need negative numbers, simply set a negative minimum — the generator handles ranges that cross zero without any extra steps.

Frequently asked questions

Is the randomness truly random?
The generator uses your browser's Web Crypto API (crypto.getRandomValues), which produces cryptographically strong random values seeded by the operating system. To avoid modulo bias it rejects any raw value that would skew the distribution, so every number in your range is equally likely. If Web Crypto is unavailable it falls back to Math.random, which is still uniform but not cryptographic.
Why can't I draw more numbers than the range allows without duplicates?
When duplicates are turned off, each number can appear only once. If you ask for ten numbers but the range only contains six possible values, four of the picks would have nothing left to draw. The tool checks this before generating and asks you to widen the range or lower the count.
What is the largest set of numbers I can generate at once?
You can draw up to 1000 numbers in a single batch. That keeps the result list readable and the page responsive. For larger samples, run the generator more than once and combine the batches.
Does this tool send my numbers anywhere?
No. Every number is generated by JavaScript running in your browser. Nothing is uploaded, logged, or stored on a server, and the results disappear when you close or refresh the page.
Can I use this to pick lottery numbers or for a giveaway?
Yes, it works well for raffles, giveaways, sampling, and similar everyday picks. Turn off duplicates so each number is unique, set the range to match your ticket or entry numbers, and generate. For high-stakes or regulated draws you should use an audited system, but for casual use this is fair and unbiased.

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