Math Calculators

Prime Number Calculator

Check primality, list a range, find neighboring primes, or factor an integer.

Explore ordinary browser-sized integers with efficient trial division and a bounded sieve.

Calculate with the Prime Number Calculator

Enter the values below. Invalid mathematical operations are explained before a result is shown.

How to use the Prime Number Calculator

  1. Choose a calculation mode when one is available.
  2. Enter the required values using the examples and field notes as a guide.
  3. Select Calculate or press Enter.
  4. Review the primary result, supporting values, and working.

Worked example

97 has no divisor through √97 and is prime.

Assumptions

The calculator uses real-number arithmetic unless complex square or quadratic roots are explicitly shown. Decimal displays can be rounded while calculations retain normal browser numeric precision.

Limitations

  • Absolute values are limited to 10,000,000 and range spans to 200,000.
  • This is not a cryptographic primality test.

Frequently asked questions

Does the Prime Number Calculator accept decimals and negative values?

It accepts them wherever the selected operation permits. Invalid domains are identified before a result is shown.

How are decimal results rounded?

Calculations retain JavaScript numeric precision and display a readable number of significant digits. A displayed decimal may therefore be rounded.

Are entries stored?

No. The calculation runs in your browser and this page does not store the values you enter.