Big Number Calculator
Arbitrary-precision integer and decimal calculator: add, sub, mul, div, mod, pow, gcd, lcm, factorial.
About this tool
A two-operand calculator that auto-detects integers vs decimals. Integers use System.Numerics.BigInteger so 1000! and 2^10000 compute exactly; decimals use a hand-rolled BigDecimal so 0.1 + 0.2 = 0.3. Pick the operation, optional precision for division, and a history list tracks every result.