Free interactive computer-science tools
Small, fast tools that run entirely in your browser. Nothing you type is sent anywhere, and there is nothing to sign up for.
- Tool
Truth table generator
Expression in, truth table out: with DNF, CNF, a minimal form and LaTeX.
Try it: Boolean-expression parser and truth-table generator - Tool
Graph traversal visualiser
Draw a graph, then animate BFS, DFS and Dijkstra with the frontier shown.
Try it: Drawable graph with BFS, DFS and Dijkstra animation - Tool
Recursion tree visualiser
Paste a recursive function or a recurrence and see its call tree and call count.
Try it: Call-tree drawer for JavaScript functions and recurrences
Private by design
Each tool is a single page of JavaScript that runs entirely on your device. Nothing you type is uploaded, there are no accounts, and the pages work offline once loaded. Code you paste into the recursion tree visualiser runs in an isolated Web Worker with a time limit, so it cannot freeze the page.
Built for teaching
The tools show their working: the truth-table generator adds a column for every sub-expression, the graph visualiser highlights each line of pseudocode as it runs, and the recursion tree visualiser counts every call. They are designed to be projected in a lecture or used to check homework by hand. Each one links to an explainer that covers the theory behind it.