Prime checker
Check primality, list prime factors and find the next prime.
Enter your values, then choose Calculate.
Limits
- Integers from 0 to 1,000,000,000. The next-prime search is limited to 10,000 candidates. Approximate real-number outputs use 12 significant digits unless a unit specifies otherwise.
- Desktop limits are provisional. Physical mobile and Safari verification remains open.
What happens to your data
Prime checker runs inside this browser tab, and the page's code comes from this site. There is no application server to receive your data, and the site's security policy limits connections to this site.
Good to know
- Integers from 0 to 1,000,000,000. The next-prime search is limited to 10,000 candidates. Approximate real-number outputs use 12 significant digits unless a unit specifies otherwise.
- Desktop limits are provisional. Physical mobile and Safari verification remains open.