Random Number Generator

Free Random Number Generator - Fast, Seeded, and Flexible

Generate high-quality random numbers for testing, simulations, class demos, and quick utilities. Choose a distribution (uniform, normal, exponential, or Poisson), set your range and decimal precision, and produce a list you can copy or export. Everything runs in your browser for privacy and speed; no uploads, accounts, or plugins. If you also build randomized text and IDs, pair this with Random Word Generator and Random Number Generator.

Key features

• Distributions: uniform for equal likelihood, normal for bell-curve values around a midpoint, exponential for time-between-events, and Poisson for counts per interval.
• Range and precision: pick minimum, maximum, and decimal places. If you enter them reversed, the tool automatically normalizes the range; a zero-width range yields a constant as expected.
• Seeded output: add an optional seed so the same settings always reproduce the same list. Ideal for tutorials, regression tests, or shared exercises.
• Unique results: enable a toggle to avoid duplicates. If you ask for more unique integers than the range permits, the tool explains the limit so you can adjust.
• Patterns for IDs: use # for digits, @ for letters, and ? for alphanumeric characters to create structured tokens such as INV-#### or ###-###-####.
• Output formats: display as decimal, binary, octal, or hexadecimal. Useful for parser tests and low-level examples.
• Share and export: settings are encoded in the URL for easy sharing; download results as CSV or JSON with one click.

Need text formatting before or after numeric generation? Use Case Converter, Word Counter, or Word Combiner for adjacent workflows.

How to use

1. Enter how many values you want to generate.
2. Set minimum, maximum, and the number of decimal places.
3. Pick a distribution: uniform for random sampling across the range; normal for values clustered near the midpoint; exponential for positively skewed samples; Poisson for event counts.
4. Optional: type a seed for reproducible output, switch on unique results to prevent duplicates, choose an output format, or add a pattern to build IDs.
5. Press Generate. Click any value to copy it, or export the whole set to CSV/JSON.

When to use each distribution

Use uniform when every value in your range should be equally likely, such as raffle draws or randomized ordering. Choose normal for measurements that cluster around an average, like height samples or sensor noise. Exponential models the time until an event occurs and is common in queueing examples and reliability sketches. Poisson is best for counts per fixed interval - arrivals per minute, defects per batch, or clicks per page. If your range is tight, the tool clamps normal values within bounds; near edges the shape becomes a truncated bell, which is expected.

For puzzle-style generation where letters matter more than number distributions, check Word Finder, Anagram Solver, and Cryptogram Solver.

Notes and limits

• This tool is not for cryptographic or security-sensitive work. For secrets or money, use a CSPRNG.
• Uniqueness is enforced on the displayed value. If you round to two decimals, two draws that round to the same string count as duplicates.
• Large lists are paged so the interface stays responsive even with thousands of results.

FAQ

What does the seed do?

The seed initializes the generator so that the same seed plus the same settings produce the same sequence. Remove the seed for fresh randomness on each run.

Why did I get fewer numbers with "unique" on?

If you request more unique integers than exist in the chosen range, the generator stops early and explains the maximum possible unique values so you can widen the range or lower the count.

Can I generate IDs instead of plain numbers?

Yes. Add a pattern like AB@@-## or ###-###-####. Patterns work with seeds and the uniqueness toggle, which helps when minting sample IDs or coupons.

Related Tools

• Sudoku Solver for number-grid solving and logic testing.
• Caesar Cipher Encoder Decoder for encoded text experiments.
• Morse Code Translator when switching between text and signal-style output.
• Mirror Text Generator for reverse and mirrored text formatting.