Memory Model Visualizer

See How Memory Works

Interactive visualization of stack vs heap memory allocation. Understand what happens when you write code like let x = y or pass objects to functions.

Scenario:

Primitives vs References

See the fundamental difference between primitive values and object references.

beginnerprimitives

Speed:Normal

Pseudocode

1x = 5
2y = x
3y = 10
4 
5obj1 = { value: 5 }
6obj2 = obj1
7obj2.value = 10

Memory State

Stack

Heap

Reference

Stack Memory

Global Frame

No variables

Heap Memory

Heap is empty

Step 1 of 7

Program starts. Stack contains global frame, heap is empty.

Learning Objectives

Primitives store values directly in stack
Objects store data in heap with references in stack
Copying primitives creates independent values
Copying references creates aliases (both point to same object)

What You'll Learn

Stack vs Heap Memory

Understand where variables and objects are stored, and why it matters for your code.

Pass by Value vs Reference

See the difference between copying primitives and copying references to objects.

Object Aliasing

Learn why modifying one variable can affect another, and how to avoid aliasing bugs.

Function Call Mechanics

Watch stack frames being created and destroyed as functions are called.