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Big Number Calculator
Do exact arithmetic on very large whole numbers that ordinary calculators cannot handle, such as numbers with 20, 30 or more digits.
About the Big Number Calculator
Do exact arithmetic on very large whole numbers that ordinary calculators cannot handle, such as numbers with 20, 30 or more digits.
How to use the Big Number Calculator
- Enter A First Large Number and B Second Large Number, using digits only.
- Choose an operation: add, subtract, multiply, divide, modulo or power.
- Read the exact result. The example buttons load sample numbers such as 2⁶⁴.
Formula and method
The calculator uses arbitrary-precision integer arithmetic, so every digit of the result is exact instead of being rounded to a floating-point approximation.
Worked example
2⁶⁴ = 18,446,744,073,709,551,616. Adding 1 to 99999999999999999999999 gives exactly 100000000000000000000000.
Tips
- Ordinary calculators lose accuracy above about 15 digits.
- Division gives the whole-number quotient. Use modulo to get the remainder.
Frequently asked questions
Why do normal calculators round big numbers?
They store numbers in a fixed number of bits, which can only represent about 15 to 17 significant digits exactly.