This piece of portable software is made to assist calculations of RSA and other cryptosystem exercises intended to be done by hand. It is written to allow and encourage understanding of code rather than efficiently do the job.

The main function is calculation of RSA key pairs along with supplementary information. Side features also include:

• building multiplicative group of keys (modulo L(N) where L is generic Euler function);
• building multiplicative group modulo N;
• evaluating any numeric expression in js. That comes into use on mobile devices that has no dev tools in browser.

You may download the only code file rsa.html from code directly or from latest release. Just keep in mind that releases here are often a bit outdated.

Consider using hosted version if it is available to the time or download code from the latest release here on github.