Skip to content
Interactive, web-based visual math assistant
Branch: master
Clone or download
Fetching latest commit…
Cannot retrieve the latest commit at this time.
Type Name Latest commit message Commit time
Failed to load latest commit information.


Prooftoys is a visual proof assistant and the engine behind Mathtoys ( The Prooftoys implementation is based on Alonzo Church's simple type theory as formulated by Professor Peter Andrews under the name Q0. Simple type theory is suitable for construction of most of mathematics, comparable to first-order logic plus set theory. It uses a minimum of simple, understandable concepts, expressing them with a handful of axioms and inference rules.

Prooftoys is implemented in JavaScript running in the user's web browser. It is designed to be highly interactive and delivered to users through the Web, so they can play with it instantly. Prooftoys has a web site with pages for interacting with it at

This repo used to have the assets for the website, but files related to the webiste are now at

Mathtoys is an interface to Prooftoys tuned for working high school algebra problems. Its unique HTML and code is also on GitHub at

You can’t perform that action at this time.