Prime Number Checker
MATHEMATICS
Prime Number Checker
Check whether an integer is prime, composite or neither.
UNDERSTAND YOUR RESULT
How it works
Check whether an integer is prime, composite or neither.
THE CALCULATIONtest divisors up to the square root
Using this calculator
Enter integer. test divisors up to the square root.
What to keep in mind
Calculations use finite real numbers. Intermediate values are unrounded; very large or undefined results are rejected.
Frequently asked questions
Are my entries saved?
No. Calculator inputs remain in the current page and are cleared when you reload or leave. The tools do not upload your entries.
Why are results rounded?
The display is rounded for readability. Calculations use unrounded intermediate values. An estimate should not be interpreted as an exact measurement.