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Random Number Generator

Generate truly random numbers with your custom min/max range. Toggle decimals, prevent duplicates, sort results, and export up to 1,000 numbers instantly.

FreeCustom RangeNo DuplicatesUp to 1,000

Range & Quantity

Options

Result

10 numbers

Min: 4 · Max: 80 · Avg: 29.40

10 Numbers

8127610804667922
Numbers are generated using cryptographically secure crypto.getRandomValues() — not Math.random().

True random vs pseudo-random

Most random number generators in programming use pseudo-random algorithms (like Math.random()) that produce deterministic sequences from a seed. This tool uses crypto.getRandomValues() — a cryptographically secure source based on hardware entropy — making the output genuinely unpredictable and suitable for security-sensitive applications.

Use cases for random numbers

  • Lottery / raffles: Generate unique numbers in a range with no duplicates.
  • Games and simulations: Dice rolls, card draws, RPG encounters.
  • Random sampling: Pick N items from a numbered list.
  • Testing and development: Generate test data within specific ranges.
  • Statistics: Generate random samples for calculations.

The 'no duplicates' algorithm

For integer ranges, the no-duplicates mode uses a Fisher-Yates shuffle on the full range array, then takes the first N values. This guarantees true uniform distribution with no repetition. For decimal numbers, duplicates are exceedingly rare given the precision of floating-point arithmetic.