Random Number Generator
Generate random integers or decimals within any range. Includes dice roll, coin flip, and Lotto number presets. Optional no-duplicates mode.
How to Use
- Set a minimum and maximum range, choose how many numbers to generate, and click Generate.
- Toggle between integers and decimal numbers.
- Enable "No duplicates" to ensure each number appears only once (useful for lottery draws).
- Use the quick presets: 1 Dice, 2 Dice, Coin Flip, Lotto 6, or 0–100%.
The Extended Calculator adds a histogram of results, multi-die rolling, card drawing from a 52-card deck, and SA Lotto/PowerBall quick picks. The Professional Calculator adds custom probability distributions (Normal, Exponential, Triangular), weighted random selection, and mathematical sequence generation.
How Random Numbers Are Generated
Integer: Math.floor(Math.random() × (max − min + 1)) + min
Decimal: Math.random() × (max − min) + min
Uniform distribution: Each value in the range is equally likely
Normal distribution: Box-Muller transform using two uniform samples
Unique numbers: Fisher-Yates shuffle on the full range
Use Cases
Dice simulation: Min=1, Max=6, Integer → one die roll
Coin flip: Min=0, Max=1, Integer → 0=Tails, 1=Heads
SA Lotto: Min=1, Max=52, Count=6, Unique → 6 unique lotto numbers
Random winner from 30: Min=1, Max=30, Count=1
Normal distribution: Use Professional tab with μ=50, σ=15