CodeVision · See your code think
Phase 1 · JavaScript Visualizer

See how your code actually runs

CodeVision animates the call stack, memory heap, event loop, and queues step-by-step — so you can finally see why async code behaves the way it does.

Call Stack

Watch frames push and pop in real time as functions execute.

Heap & GC

See objects allocated, referenced, and garbage-collected.

Event Loop

Microtasks, macrotasks, Web APIs — finally make sense.

More modules coming: React render cycle · Next.js SSR/CSR · DBMS · Network