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Random Number Generator

Configuration

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Enter values to see the random generation method.

What Your Result Means

How This Calculator Works

This random number generator uses the JavaScript Math.random() function, which produces cryptographically-suitable pseudo-random numbers between 0 and 1. The calculator scales and shifts these values to your specified range, then rounds or truncates as needed. For integers, it uses Math.floor() to ensure whole numbers. For decimals, toFixed() ensures the correct precision.

Quick Questions

Why do I get duplicates when I disabled them?

When requesting more unique numbers than possible in your range (e.g., 50 unique numbers from 1-10), the generator allows duplicates rather than failing. This is shown with a warning message.

Is this cryptographically secure?

Math.random() is suitable for games, simulations, and random selection. For security-sensitive applications (encryption, tokens), use a dedicated library like crypto.getRandomValues().

Can I generate negative numbers?

Yes. Set your minimum to any negative value and maximum to any higher value. The calculator handles negative ranges automatically.

Sources

Method & review

MethodologyHow we calculate this Reviewed & Updated2026-04 Next review2027-04

Estimate only. Results reflect your inputs and standard formulas. Double-check important decisions independently.