Random Number Generator
Generate random integers or decimals within a range, including very large numbers with arbitrary-precision support.
About this calculator
Generate random integers or decimals within a range you choose, from a single quick pick to a batch of many numbers with arbitrary precision.
Simple mode produces one whole number between a lower and upper limit — both limits support numbers with thousands of digits, since the generator works directly with arbitrary-precision integers rather than standard floating-point numbers. Comprehensive mode produces one or many numbers at once, either whole numbers or decimals with a fixed number of digits after the decimal point (up to 999). Every value is drawn uniformly from the chosen range using the browser's cryptographically strong random number source, so results are unbiased and unpredictable.
How to use
- Choose a generator mode: Simple for a single random integer, or Comprehensive for more control.
- Enter a lower and upper limit.
- In Comprehensive mode, also set how many numbers to generate and choose Integer or Decimal.
- For Decimal results, set the precision — the number of digits to show after the decimal point.
- Press Generate to produce the numbers, or Clear to reset the form.
Tips
- Both modes accept negative limits and numbers far beyond what a standard calculator can represent precisely.
- Use Copy All to copy every generated number at once.