Arbitrary-precision integer tools used throughout cryptography and number theory — GCD, LCM, modular inverse, modular exponentiation, the extended Euclidean algorithm, and the Chinese Remainder Theorem. Powered by BigInt, so inputs of thousands of digits work fine.
All inputs accept arbitrary-precision decimal integers (optionally 0x… for hex, 0b… for binary). Negative numbers are supported where mathematically meaningful; modular inverse requires gcd(a, m) = 1. Chinese Remainder accepts comma-separated residues and moduli and requires pairwise coprime moduli.