Stack and Queue Visualizer

Compare LIFO stack operations with FIFO queue operations using the same values, highlighted top/front/rear positions, and live operation output.

Items
4
Top
40
Front
10
Rear
40

Structure input

The first value is the queue front. The final value is the stack top and queue rear.

Operations

Stack and queue diagrams

Sample structures loaded. Push, pop, enqueue, dequeue, or peek to compare access rules.

Stack

LIFO
40
top
30
index 2
20
index 1
10
index 0

Queue

FIFO
10
front
->
20
i 1
->
30
i 2
->
40
rear

Operation output

Sample structures loaded. Push, pop, enqueue, dequeue, or peek to compare access rules.

Current state

[10, 20, 30, 40]

What is a Stack and Queue Visualizer?

A stack and queue visualizer shows how the same values behave under two access rules. A stack uses LIFO order, which means last in, first out. A queue uses FIFO order, which means first in, first out.

This tool renders both structures together so you can compare push, pop, enqueue, dequeue, and peek operations without switching pages.

For the full cluster of related tools, browse the Data Structure Visualizers hub.

How to use this stack and queue visualizer

  • Paste values such as [10, 20, 30, 40].
  • Click Build structures to render a stack and queue.
  • Use push and pop to practice stack behavior.
  • Use enqueue and dequeue to practice queue behavior.
  • Use peek actions to inspect the next item removed without changing the structure.

The visualizer keeps both views synchronized because the goal is to compare access rules on the same ordered collection.

Stack and queue in algorithms

Stacks are common in recursion simulation, expression parsing, undo history, and depth-first search. Queues are common in scheduling, buffering, breadth-first search, and level-order tree traversal.

If you want to see queues inside graph traversal, try the Graph BFS DFS Visualizer or Matrix Traversal Visualizer. To connect stack frames with recursive function calls, use the Recursion Tree Visualizer or Backtracking Visualizer. If you want node pointers instead of array-style storage, use the Linked List Visualizer.

Frequently Asked Questions

What is LIFO?
LIFO means last in, first out. The newest item is removed first from a stack.
What is FIFO?
FIFO means first in, first out. The oldest item is removed first from a queue.
Can I paste my own stack or queue values?
Yes. Paste an array, comma-separated list, or space-separated list. The first value becomes the queue front, and the final value becomes the stack top.
Does push do the same thing as enqueue?
Both add a value to the end of the collection in this visualizer. The difference appears when removing values: stack pop removes from the end, while queue dequeue removes from the front.

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