Random Number Generator

Generate exact random integers with exclusions, no repeats and local TXT or JSON downloads.

Generate up to 1,000 integers locally with Web Crypto. Both bounds are included.

Minimum

Maximum

Count

No repeatsSort ascending

Exclude specific numbers (optional)

Excluded integers, separated by commas or spaces

For sampling and everyday choices—not password generation, certified lotteries or audited prize draws. Input changes clear the previous result.

This tool runs entirely in your browser. Your data is never uploaded, never stored, and never leaves your device.

Generate up to 1,000 exact random integers with Web Crypto, optional exclusions, no-repeat sampling and local TXT or JSON downloads.

How to use it

1Set inclusive integer bounds and the number of results.
2Choose repeat and sorting options; optionally exclude specific values.
3Generate and review the results, then copy or download them.

What happens to your data

Generation stays in your browser. This is an integer sampler, not a password generator or certified, publicly auditable draw service.

Last updated October 2026

Generate random integers between inclusive minimum and maximum values, choose whether repeats are allowed, and exclude specific numbers without uploading a list. Produce up to 1,000 results, optionally sort them, then copy or download them as plain text or JSON. This is useful for test data, classroom exercises and everyday selections where you need a clear range and a reproducible record of the output—not a promise that a particular result will appear.

The generator uses your browser’s Web Crypto random source rather than Math.random. Rejection sampling avoids the modulo bias that can give some integers a higher chance than others. Unique mode samples without replacement using a bounded mapping, so choosing most of a range does not leave the page repeatedly guessing already-picked values.

How it works

Enter whole decimal integers from −9007199254740991 through 9007199254740991. Both endpoints are included. Internal integer arithmetic preserves the exact range even when its width is larger than JavaScript’s largest safe Number. Fractions, scientific notation and out-of-range values are rejected. Count is limited to 1–1,000; exclusions are limited to 1,000 comma- or whitespace-separated integers inside the selected range. Duplicate exclusions count once.

With No repeats selected, the requested count cannot exceed the number of remaining candidates. Excluding every candidate is an error. Sorting changes only presentation, not which numbers were selected. A range containing one available number will always return that number; allowing repeats does not mean that repeats must occur in every sample. Editing any setting clears the old result so it cannot be mistaken for a newly generated answer.

Numbers are generated locally and are not sent to a random-number service. TXT exports contain one integer per line. JSON exports deliberately use decimal strings to preserve digits in applications with smaller numeric limits. Spreadsheet software can round large numbers even when they look correct in a browser: import them as text if exact digits matter. This tool does not provide a seed for replaying a sequence, a public audit trail, certified lottery draws, password generation or regulated gambling compliance. Use a purpose-built system for those tasks.

Worked example: a constrained set with no uncertain outcome

Input: Minimum 1; maximum 5; count 3; no repeats; sorted; exclusions 2, 4
Result: 1, 3, 5

All three remaining candidates must be selected. With a smaller count, the result is random and can differ.

Common use cases

Selecting numbered test cases without replacement
Creating small random integer datasets locally
Excluding already-used choices from a bounded range
Keeping a text or JSON record of a generated sample

Frequently asked questions

Are the minimum and maximum included?＋

Yes. A range from 1 to 10 includes both 1 and 10. Explicitly excluded values are removed from the candidate set before sampling.

How do I generate random numbers without duplicates?＋

Leave No repeats selected and keep the count no greater than the number of candidates after exclusions. The tool samples without replacement and reports an error when the requested unique count is impossible.

Is this a true random number generator?＋

It uses the browser’s cryptographically strong pseudorandom Web Crypto source. This is not a claim of direct hardware randomness, independent certification or a publicly auditable draw. Rejection sampling avoids a range-mapping bias.

Why does JSON contain quoted numbers?＋

Decimal strings preserve all digits when another application parses the file. Some programs round large numeric values. Convert strings to numbers only when the receiving system supports the full range exactly.

Can this generate passwords or certified prize draws?＋

No. Password policies and auditable draws require additional safeguards this integer sampler does not provide. Use an appropriate dedicated password generator or independently audited draw process.