Maths & numbers

Chinese remainder solver

Solve compatible integer congruences, including non-coprime moduli.

Chinese remainder solver
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Combines up to 20 congruences using the extended Euclidean algorithm with exact BigInt arithmetic. Each modulus must be positive, and shared-factor congruences must be compatible. Returns the smallest non-negative solution and the combined least-common-multiple modulus. Input integers have at most 80 digits; the final modulus is bounded to 500 digits.

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Worked example

A fixed demonstration, separate from the values you enter above.

One remainder,modulus pair per line
2,3
3,5
2,7

Example result

Smallest non-negative solution
23
Combined modulus
105

All solutions are x + k × combined modulus, for integer k. Compatible non-coprime moduli are supported with exact BigInt arithmetic.