🔢 Math Tool

Big Number Calculator

Perform exact arithmetic on integers of any size — millions of digits — using JavaScript BigInt. Supports addition, subtraction, multiplication, division, modulo, powers, GCF, LCM, and factorial.

Enter Big Numbers

Enter big integers and select an operation
Uses JavaScript BigInt for exact integer arithmetic — no floating-point errors.

Frequently Asked Questions

Why does regular arithmetic fail for big numbers?
JavaScript (and most languages) use 64-bit floating-point numbers (IEEE 754), which have only about 15-17 significant decimal digits of precision. Numbers beyond ~9 quadrillion lose precision. BigInt stores and computes exact integers of unlimited size.
What is the largest factorial I can compute?
There is no hard limit — 1000! (a 2568-digit number) computes in under a second. Very large factorials (e.g. 100,000!) may take several seconds. For powers, the exponent B should be a reasonable size (e.g. under 10,000).