Affine Cipher Encoder

Encode Affine Cipher data online. Read the input conventions, configure the available options and copy or download the result in your browser.

Free · No sign-up required

Text input

Your result is ready to copy or download after running.

Tool options

About Affine Cipher Encoder

The Affine cipher is a type of monoalphabetic substitution cipher, wherein each letter in an alphabet is mapped to its numeric equivalent, encrypted using simple mathematical function, (ax + b) % 26, and converted back to a letter.

Input: text. Output: text.

Format reference: Affine Cipher Encode background and specification

Example

Use “Try example” to load this public sample and its settings, then run it.

Settings used in this example
ParameterExample valueInput and choices
a23Number
b23Number

Input

some keys are shaped as locks. index[me]

Result

vhnl tldv xyl vcxelo xv qhrtv. zkolg[nl]

Parameters

ParameterDefault valueInput and choices
a1Number
b0Number

Before interpreting the result

Use the exact key encoding, mode, padding and IV expected by the source system. Historical ciphers are useful for learning and analysis. Encoding alone provides no confidentiality.

How to use this page

  1. Paste your input or open a local file.
  2. Adjust tool options if needed, then choose Run tool.
  3. Copy the result or download the original output bytes.

Inputs and results are not added to the public catalogue or saved in the URL. Processing happens in your browser; HTTP Request and DNS over HTTPS send the requests you explicitly run. Files up to 128 MiB can be opened; decompression and image tools may have smaller processing limits. Large results have a shortened preview. Text and HTML downloads use UTF-8; binary downloads preserve output bytes. Pasted text follows browser newline handling; open a file when exact input bytes matter.

Related tools

Browse encryption / encoding tools