Math
Extended GCD / Modular Inverse
Compute the extended GCD, Bézout coefficients, and modular inverse when it exists. Educational BigInt calculator.
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Non-zero modulus.
gcd(a, m)
Bézout x (a·x + m·y = gcd)
Bézout y
Modular inverse (if gcd = 1)
This free Extended GCD / Modular Inverse covers Compute the extended GCD, Bézout coefficients, and modular inverse when it exists. Educational BigInt calculator.
Enter the Extended GCD / Modular Inverse fields, then read the output. Math calculators on this site keep the formula visible beside the form, with no account required.
Using the Extended GCD / Modular Inverse
Compute the extended GCD, Bézout coefficients, and modular inverse when it exists. Educational BigInt calculator. Typical inputs are a and Modulus m. How it works beside the form states the identity the Extended GCD / Modular Inverse applies.
FAQ
How do I use the Extended GCD / Modular Inverse?
Open the Extended GCD / Modular Inverse, fill a and Modulus m, and read the result. Enter a and modulus m. If gcd ≠ 1, no modular inverse exists (shown as —). Related: Modular Exponentiation, Toy RSA Demonstrator.
What formula does the Extended GCD / Modular Inverse use?
The Extended GCD / Modular Inverse uses the identity in How it works. In words: Enter a and modulus m. If gcd ≠ 1, no modular inverse exists (shown as —). Related: Modular Exponentiation, Toy RSA Demonstrator.