Big Number Calculator
Perform addition, subtraction, multiplication, division and powers on integers of any size — beyond standard JavaScript number precision.
Single Number Analysis
How to use the Big Number Calculator
- Enter your inputs into the Big Number Calculator above.
- Results update instantly as you type — no submit button needed.
- Adjust any value to see how the result changes in real time.
The big number approach
Use BigInt or arbitrary-precision libraries for exact arithmetic with integers of any size
Standard floating-point numbers have ~15 digits of precision. BigInt and arbitrary-precision libraries allow exact arithmetic on integers with thousands of digits.
Worked example
100! (100 factorial) = 9.3326...×10¹⁵⁷ — far beyond standard double precision. Big-number arithmetic computes the exact 158-digit result: 93326215443944152681699238856266700490715968264381621468592963895217599993229915608941463976156518286253697920827223758251185210916864000000000000000000000000.
Frequently asked questions
Why aren't big numbers the default?
Big-number arithmetic is much slower than fixed-precision floats. Standard 64-bit doubles handle billions of operations per second; big numbers can be 100–1000× slower.
When do I need big numbers?
Cryptography (RSA uses 2048-bit primes), combinatorics with large n, scientific computation requiring exact integer arithmetic, financial calculations requiring exact decimals.
Can I do non-integer big numbers?
Yes — libraries like decimal.js support arbitrary-precision decimals. They're typically slower than BigInt but handle fractions exactly without binary-decimal conversion errors.