How to use this calculator
Select Calculate again for a new sample. Rejection sampling removes modulo bias from browser-generated random bytes. Unique mode samples without replacement and randomly orders the selected numbers.
- Enter number type, minimum, maximum and review the remaining options.
- Select Calculate or change a value to update the result. Read the result label and units before copying.
- Use Reset to restore the worked starting values.
Formula and method
Uniform crypto sampling; not a password/key generator. Up to 999 digits per bound and 999 decimal places, at most 1,000 draws. Decimal mode samples a fixed decimal grid, including both representable endpoints.
Worked example
Minimum 1 and maximum 6 simulate a six-sided die.
Questions about random number generator
Can a generated number repeat?
Repeats are allowed by default. Select Unique numbers only to sample without replacement within a batch. Quantity can be up to 1,000 but cannot exceed the range size in unique mode. Each new batch starts fresh; previous batches are not excluded.
What assumptions should I check?
Uniform crypto sampling; not a password/key generator. Up to 999 digits per bound and 999 decimal places, at most 1,000 draws. Decimal mode samples a fixed decimal grid, including both representable endpoints.
Are my inputs saved?
Calculations run in your browser. We store only tool IDs for favorites and recent tools. A calculation link contains your inputs only when you explicitly choose to copy one.