Random Number Generator
Generate random numbers in any range, with or without duplicates
About Random Number Generator
Generates random numbers in a range you set, with optional decimals, and has presets for dice (such as 2d6), coin flips, lottery tickets (pick 6 of 49) and picking or shuffling items from a list you paste.
Pick a mode. In Numbers, set the minimum, maximum and how many, choose decimal places (0 for whole numbers), and turn on "no duplicates" or "sort" if you need them. In Dice, type NdM such as 2d6, d20 or 3d8+2. In Lottery, set how many numbers to pick from how big a pool. In List, paste one item per line and pick some or shuffle them all. Whole numbers go up to very large ranges, and up to 10,000 results at a time. If the minimum is higher than the maximum the two are swapped for you. The numbers appear straight away; copying or downloading them takes one of your trial uses.
By default the numbers come from your browser's crypto.getRandomValues, a cryptographically secure source, and every value in the range is equally likely. The optional seed switches to a repeatable generator that is NOT secure (anyone with the seed can recreate the list), so use it for reproducible classroom draws or test data, never for a raffle or a secret.
Watch: Random Number Generator in Action
- Is this random enough to trust for something like a raffle drawing?
- Yes, as long as the seed box is empty. Then the numbers come from your browser's crypto.getRandomValues, a cryptographically secure source, and the tool throws away any draw that would favour some values, so every value in your range is equally likely. If you type a seed the tool switches to a repeatable generator (sfc32) that is not secure, and says so beside the result: anyone with the seed can recreate the list, so never use a seed for a raffle.
- Can it give decimals, such as 0.5 to 1.5 with 3 decimal places?
- Yes. Set Decimal places (0 to 10). The tool picks from every number with that many decimals between your minimum and maximum, both ends included, so 0.5 to 1.5 with 3 places chooses from 1,001 values. A limit with more decimals than you allowed is rounded inward: the minimum up and the maximum down, never outside what you typed.
- Can it roll dice, flip a coin, pick lottery numbers or choose from a list?
- Yes. Dice takes NdM such as 2d6, d20 or 3d8+2 and shows each die and the total. Coin flips up to 10,000 times and counts heads and tails. Lottery picks different numbers from 1 to a pool you set, sorted, so 6 of 49 gives a classic ticket; it also states the exact odds of any one ticket. List takes one item per line and draws some or shuffles all; the list never leaves your browser.
- Why does it say it is not possible to get 6 unique numbers from 1 to 5?
- Because only 5 different values exist there. The message says how many values the range holds and what to change: lower How many, widen the range, allow more decimal places or turn off No duplicates.
- Does generating use up one of my trial uses?
- No. Numbers appear straight away. A trial use is taken when you copy or download them, once for the same numbers in a visit; a new draw is a new output.
How to use Random Number Generator
Choose Numbers, Dice, Coin, Lottery or List. For numbers, set your minimum and maximum, how many you want and how many decimal places (0 for whole numbers), then click generate. If you need every result to be unique (no repeated numbers in the same batch), toggle the "no duplicates" option before generating — without it, the same number can appear more than once in a single batch, which is expected default behavior for genuine independent random draws, similar to rolling the same die value twice in a row being entirely normal.
When to use it
Useful for any situation needing a genuinely random selection — picking a winner from a numbered raffle or giveaway, randomly selecting a sample from a numbered list for a survey or audit, generating random test data for a spreadsheet or database, or settling something with an agreed-upon random draw rather than a subjective choice.
When not to use it
For generating a large, statistically rigorous random sample for formal research or scientific purposes, a dedicated statistical software package with documented, peer-reviewed random sampling methodology is more appropriate than a general-purpose web tool — this tool is built for everyday practical randomness (raffles, quick decisions, casual sampling), not formal statistical research requiring documented methodology.
Tips for best results
For anything where the fairness of the randomness genuinely matters to people relying on the result — a raffle drawing with real prizes, for instance — this tool's use of your browser's cryptographically secure random source (rather than a simpler, more predictable pseudo-random method some tools use) is worth explicitly mentioning to participants, since it's a genuinely stronger randomness guarantee than many casual random-number tools provide.
Limitations
Requesting more unique numbers than actually exist in your specified range (asking for 50 unique numbers between 1 and 20, for instance) isn't mathematically possible — the tool will indicate this rather than silently returning fewer numbers than requested or duplicate values despite the no-duplicates setting.
Privacy
Generation happens entirely in your browser using your browser's own cryptographically secure random number source — nothing about your generated numbers or chosen range is sent to or stored on any server.
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