Affine Cipher Decoder - Free, Instant, In Your Browser
Enter the encoded text and the same keys A and B used to encode it.
How to use Affine Cipher Decode
- 1Enter the required date(s) and details above.
- 2Click Calculate - Affine Cipher Decode runs instantly, right in your browser.
- 3Read your result below.
Your file is processed in your browser and is never uploaded.
Frequently Asked Questions
What's the formula?
Each letter value y is mapped back to A⁻¹ × (y − B) mod 26, using the modular inverse of A.
Is my data sent to a server?
No - everything runs entirely in your browser with JavaScript. Nothing is uploaded.