Prime Number Checker

Math guide

How to use the Prime Number Checker

Check whether a whole number is prime. The page also explains the prime check and shows a practical example: 29 is prime; 30 is not prime.

  1. 1

    Enter your details

    Enter the values for the prime number checker scenario you want to check.

  2. 2

    Check the calculation

    Review the result alongside the prime check: A prime number has exactly two positive divisors: 1 and itself.

  3. 3

    Compare scenarios

    Change one or more inputs to see how they affect the prime Number Checker result before you use the estimate.