Big Number Calculator
Do exact arithmetic on whole numbers that are far too large for an ordinary calculator. Enter integers of any length, pick an operation, and get the full result with every digit, no scientific notation and no rounding.
How to use the big number calculator
- Type your first integer (it can be hundreds of digits long).
- Choose an operation and, for everything except factorial, type the second integer.
- Read the full exact result, check the digit count, and copy it.
Examples
Multiply two large numbers
123456789012345678901234567890 x 2
246913578024691357802469135780
Power of two
2 ^ 256
115792089237316195423570985008687907853269984665640564039457584007913129639936
Integer division with remainder
100 / 7
14 remainder 2
Frequently asked questions
What is a big number (arbitrary precision) calculator?
It does exact math on integers of any size. A normal calculator stores numbers as 64-bit floating point and starts rounding past about 15-16 digits. This tool keeps every digit, so a 200-digit multiplication is exact.
How does it stay exact for huge numbers?
It uses JavaScript's built-in BigInt type, which represents whole numbers with as many digits as memory allows. Every operation runs on BigInt values, so there is no floating-point rounding at any step.
Which operations are supported?
Addition, subtraction, multiplication, division (returned as quotient and remainder), exponentiation (power), modulo, factorial, greatest common divisor (GCD) and least common multiple (LCM).
Why must the inputs be whole numbers?
BigInt only represents integers, which is what makes the results exact. Decimals, fractions and exponents are rejected. You may include a leading minus sign for negative values.
Is there a limit on factorial?
Factorial is capped at 100000 so the page never freezes. Even within that range the results are enormous: 100! already has 158 digits. Larger inputs are rejected with a clear message instead of hanging.
How is division handled?
Division is integer division. The answer is shown as a quotient and a remainder, for example 100 / 7 gives 14 remainder 2. Dividing by zero is rejected.
Is my data private?
Yes. All calculations run locally in your browser with no numbers sent to a server, so nothing you type is stored or logged. The optional API exists for automation but the on-page tool is fully client-side.
Related tools
Prime Factorization Calculator
Break any whole number into its prime factors. Get the factorization in exponent form like 2^3 x 3^2 x 5, a factor table, and whether the number is prime.
Scientific Notation Converter
Convert numbers to and from scientific notation and E notation. Enter a number or a value like 1.23 x 10^4 to see the standard decimal form. Free and private.
GCD and LCM Calculator
Find the greatest common divisor and least common multiple of a list of integers. Enter two or more numbers separated by commas or spaces.
Area Calculator
Find the area of a circle, square, rectangle, triangle, trapezoid, parallelogram, ellipse, sector or rhombus. Free and runs in your browser.
Arithmetic Sequence Calculator
Find the nth term, the sum of n terms and the full term list for any arithmetic or geometric sequence. Enter the first term, step or ratio, and n.
Average Calculator
Find the mean, median, mode, range, sum, count, min and max of a list of numbers. Paste values separated by commas, spaces or new lines.