About this tool
Do arithmetic on whole numbers of any length with perfect precision. Enter two integers, pick an operation and get the exact result — no rounding, no scientific notation, no lost digits. It all runs in your browser.
The calculator parses your input directly into native BigInt values (no eval is ever used) and supports addition, subtraction, multiplication, integer division with remainder, modulo, exponentiation and factorial of the first operand. Division shows both the quotient and the remainder; every result also reports its exact digit count.
Use it for cryptography, combinatorics, checksums or any place where ordinary calculators overflow at about 16 digits. Division by zero, negative exponents and negative factorials are rejected, and extremely large powers or factorials are capped so the page stays responsive.