Random Number Generator

Random Number Generator produces whole numbers between a minimum and a maximum you set. Generate one for a quick decision, or a batch for a draw, a sample or a set of test values.

The unique option guarantees that no number repeats within a batch, which is what you need for a raffle, a lottery line or picking winners from a numbered list. Without it, each number is drawn independently and repeats are possible, which is the right behaviour for simulating dice rolls or coin flips where every throw is a fresh event.

Randomness comes from your browser's cryptographic random number generator with rejection sampling, so every value in the range is equally likely. That sounds like a technicality, but the usual shortcut of taking a remainder makes the lowest numbers in a range slightly more likely than the highest, which matters for a draw that has to be fair.

• Any range, including negative numbers
• Generate between 1 and 1000 values
• Unique values only, for draws and samples
• Optional sorting of the result
• Choice of separator for the output
• Uses cryptographic randomness with no modulo bias
• Clear message when a unique batch is larger than the range allows

The random number generator is used by writers, developers, students, marketers and anyone else who needs the job done once without installing software. Common cases include:

• Drawing winners from a numbered list of entrants
• Picking a lottery line
• Simulating dice rolls or coin flips
• Selecting a random sample of rows for checking
• Settling a decision when nobody can choose