jsCoq

Interactive web-based Coq theorem prover in your browser

jsCoq cover

Overview

The Coq Theorem Prover, Right in Your Browser

jsCoq is an interactive, web-based environment for the Coq Theorem Prover. No installation required — just open your browser and start proving theorems.

Key Features

  • Browser-Based — Run Coq entirely in your browser with no server-side processing
  • Interactive Proof IDE — Step through proofs with real-time goal panel tracking
  • Educational — Perfect for learning formal proofs and theorem proving
  • Rich Package Ecosystem — Includes Coq standard library, Mathematical Components, Software Foundations, and many more
  • Collaborative Development — Share proof scripts easily with a Pastebin-style scratchpad
  • Multiple Packages — Pre-loaded with init, coq-base, coq-collections, coq-arith, coq-reals, mathcomp, and more

How It Works

jsCoq brings the full power of the Coq proof assistant to the web. Use keyboard shortcuts to navigate through proofs:

  • Alt + ↓ / ↑ — Move through proof steps
  • Alt + Enter — Run to current point
  • F8 — Toggle goal panel

Perfect For

  • Learning formal methods and theorem proving
  • Teaching Coq in classrooms without installation hassles
  • Quick experimentation with proof concepts
  • Collaborative proof development

Get Started

Visit coq.vercel.app/scratchpad.html to start writing proofs immediately.

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