Random Number Generator
The honest dice roll — N integers in your range, raffle rules or dice rules, with the low, the high, and the average of what came out.
Random Number Generator
Results recalculate instantly on every keystroke. Nothing you type is transmitted.
What this result does not account for
- Results are a model, not a quotation — an institution's own figures govern.
- Every input is an assumption; change one and the answer changes with it.
- Rounding is applied only at the display layer, so totals may differ by a cent from a statement that rounds each line.
In short: 5 draws from 1 to 100, dice rules. The browser's own random source picks each one fresh — right for raffles, sweepstake orders, and settling who goes first; not cryptographic, and the page says so. The low, the high, and the average of the draws are printed beside them.
Formula
each draw = low + ⌊random × (high − low + 1)⌋; the spread prints the low, high, and mean of the draws
A random integer in [low, high] is the floor of a uniform draw scaled to the range's width — every integer in the range equally likely, each draw independent of the last. Unique mode changes the rules from dice to raffle: names leave the hat once drawn, so no value repeats. What the browser provides is a pseudorandom generator, not a cryptographic one — perfectly fair for raffles, drafts, and dinner decisions, and the honest answer for anything securing money is 'ask a cryptographer' (or use a tool built for it). The spread line shows what actually came out: the low, the high, and the mean of this roll.
Worked Example
- Set the range — low and high, inclusive.
- Set how many draws, and whether repeats are allowed.
- Roll — the draws print with their spread.
Defaults: 5 draws from 1 to 100, repeats allowed — each roll fresh, the spread printed beside it.
Strengths & Limits Of This Model
Where this engine is strong
- Runs entirely in your browser — no figure you type is transmitted or stored.
- Shows the full working, so every number can be traced and challenged.
- Free, unmetered and free of affiliate incentives.
Where it stops
- Generalised assumptions cannot capture every individual circumstance.
- Jurisdiction-specific rules and mid-year changes may not be reflected.
- A model output is not a substitute for a professional review of your position.
Practical Use Cases
Raffles
unique mode, no repeats
Draft orders
who goes first, settled
Sampling
N picks from a numbered list
Methodology & Editorial Standards
Computation runs in IEEE-754 double precision at full internal precision; rounding to two decimal places occurs strictly at the display layer, so no cumulative drift enters the result. All monetary outputs use accounting presentation — grouped thousands, two decimals, negatives in parentheses — so figures can be transcribed directly into a model or working paper. Division-by-zero and out-of-domain inputs return an em-dash rather than a misleading number.
This engine was reconciled against an independent reference implementation and hand-verified for the worked example above before release. Our full five-stage review process is published on the About Us page.
Disclaimer. This calculator is provided for informational and modelling purposes only and does not constitute financial, tax, legal, medical, or engineering advice. Verify all figures with a qualified professional before acting on them.
Random Number Generator — 8 Expert FAQs
8 analyst-written answers to the questions practitioners actually ask — optimised for voice and answer-engine retrieval.
Are the draws really random?
They come from the browser's pseudorandom generator — for everyday purposes (raffles, draft orders, picking who drives) it is exactly as fair as it needs to be: uniform over the range, no memory between draws. It is not a cryptographic source, and this page will not pretend otherwise: nobody should derive keys from it. Fair dice, not vault doors.
How does unique mode work?
Like a raffle hat: each drawn value leaves the pool, so duplicates are impossible and the draw stops when the count is met. That makes the draws dependent — after 7 comes out, the chance of 7 is zero, which is the point. The range must be big enough to hold the count: a raffle of 10 winners needs at least 10 numbers in the hat.
Why did the same number come out twice?
Because repeats were allowed — dice rules. Independent draws have no memory: the chance of a repeat on the next draw is 1 in the range's width, same as any other value. If the roll is picking winners, switch unique mode on and the repeats disappear.
Is every integer in the range equally likely?
Yes — the draw scales one uniform random value across the range's width and floors it, so each of the (high − low + 1) integers carries the same probability. No midpoint bias, no end-of-range clumping; the spread line on big rolls is the place to watch that play out: low and high converge toward the range's edges as the count grows.
What is the average line telling me?
The mean of THIS roll — not the range's midpoint, though for big rolls they land close. Five draws from 1 to 100 can average 38 or 71; twenty draws start regressing toward the middle. It is a description of the sample you are holding, which is the honest thing to print next to it.
Can I use this for a giveaway or draft order?
That is the designed job: unique mode with your entry numbers as the range is a raffle hat — no repeats, every entry even. For a draft order, draw as many numbers as participants and sort: the order the numbers arrive in IS the order. What it is not for: anything where an adversary profits from predicting the next value — that is cryptography's table, not a browser's.
Why can't the page promise the same numbers twice?
Because it is actually rolling: there is no seed you can copy, no sequence to replay, and no memory of the last roll — the flip side of genuineness is unrepeatability. If you need to reproduce a draw later (audit a raffle, settle an argument twice), the honest method is to write the results down when they land, not to look for a seed field.
What does cryptographic randomness add?
Unpredictability against an adversary, not more fairness: for a raffle among friends the browser's generator is indistinguishable from perfect; for lottery-scale money where someone profits from guessing the next value, secrets need a source designed against adversaries and reviewed by people who think about them for a living. Knowing which table you are sitting at is the whole decision.