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Education

Prime Factorization Calculator

Break whole numbers into prime factors and count their divisors.

Numbers whose second-largest prime factor exceeds about 10 million are too slow to factor in the browser.

Education

Prime Factorization Calculator

Local only
Everything stays in your browser

Your text is processed on your device — nothing is uploaded to a server.

How it works

Trial division with exact big-integer arithmetic, so large numbers stay exact. Numbers whose second-largest prime factor exceeds about 10 million are too slow to factor in the browser.

Good to know

Frequently asked questions

How do I use it?

Enter your whole numbers and press “Factorize”. Check the result, then copy or download it.

How does it work?

Trial division with exact big-integer arithmetic, so large numbers stay exact.

Are there limitations?

Numbers whose second-largest prime factor exceeds about 10 million are too slow to factor in the browser.

Is my data uploaded?

No. Everything is processed in your browser and nothing is sent to a server. No account is needed.

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