Big Number Calculator
Do exact arithmetic on numbers far too long for an ordinary calculator: hundreds of digits, huge powers and factorials.
About the Big Number Calculator
Type two whole or decimal numbers of any length and choose an operation. The calculator works with up to 1,000 digits and shows the full exact result plus scientific notation.
Everyday calculators keep about 15 significant digits. This one keeps up to 1,000, so whole-number results like 2^1000 or 500! are exact, and division and square roots are correct to 1,000 digits.
The formula
Arbitrary-precision decimal arithmetic
Worked example
2^100
- = 1,267,650,600,228,229,401,496,703,205,376
Questions people ask
How big can the numbers be?
Results are exact up to 1,000 significant digits; factorials up to 3,000! and powers up to 10,000.
Why does 0.1 + 0.2 work exactly here?
Numbers are stored as decimals, not binary fractions, so there's no binary rounding.
Where are huge numbers used?
Cryptography, combinatorics (like 52! card orders) and checking other software's arithmetic.