A* Pathfinding Visualizer — Interactive, Heuristic Search
Interactive A* pathfinding on a grid with a Manhattan heuristic — draw walls, move start/goal, generate mazes, step through the search. Runs in your browser.
Click & drag on the grid to draw walls · drag the green and red squares to move start / goal · then press Play. Want a challenge? Hit Play it yourself and solve the maze by hand.
Move the indigo token with ↑ ↓ ← → / WASD (or tap an adjacent cell) from the green start to the red goal. Walls block you.
Pseudocode
Time · Space
How to use
- 1 Draw walls by clicking and dragging; drag the green start or red goal to reposition them.
- 2 Press Play to watch A* head toward the goal using its distance heuristic.
- 3 Use Maze for instant obstacles, or Step through node by node.
- 4 Notice how few cells A* visits compared with Dijkstra or BFS.
Why use this tool
- See how the Manhattan heuristic pulls the search straight toward the goal.
- A* finds the shortest path while exploring far fewer nodes than uninformed search.
- Toggle between this and the Dijkstra / BFS visualizers to compare exploration.
- Runs entirely in your browser. No signup, no uploads.
Frequently asked questions
What is the A* algorithm?
A* (A-star) is a best-first pathfinding algorithm that orders the frontier by f = g + h, where g is the cost from the start and h is a heuristic estimate of the cost to the goal.
What heuristic does this visualizer use?
The Manhattan distance (|Δrow| + |Δcol|), which is admissible on a 4-directional grid — it never overestimates, so A* is guaranteed to find the shortest path.
What is the time complexity of A*?
In the worst case O(E log V) like Dijkstra, but with a good heuristic it explores dramatically fewer nodes in practice.
When is A* better than Dijkstra?
Whenever you have a single goal and a useful heuristic. A* focuses the search toward the goal; Dijkstra explores in all directions equally.
What is A* Pathfinding Visualizer?
An A* Pathfinding Visualizer animates the A* search algorithm on a grid. A* orders its frontier by f = g + h (cost so far plus a Manhattan-distance heuristic), so it explores toward the goal and finds the shortest path while visiting far fewer cells than uninformed search.
A* Pathfinding Visualizer is a free algorithm utility by Zerethon Tools. Interactive A* pathfinding on a grid with a Manhattan heuristic — draw walls, move start/goal, generate mazes, step through the search. Runs in your browser. Runs entirely in the browser — no signup, no upload.
- Category
- Algorithm
- Pricing
- Free
- Privacy
- Browser-based
- Signup
- Not required
Privacy
Your data never leaves your browser unless explicitly stated. A* Pathfinding Visualizer runs entirely client-side — no server upload, no logging, no tracking of your input.
New to this? Read the step-by-step explanation with Big-O analysis: Learn Graph Algorithms →
Compare
Related tools
Dijkstra's Algorithm Visualizer
Interactive Dijkstra pathfinding on a grid — draw walls, move start/goal, generate mazes, step through the search. Runs in your browser.
Open toolBreadth-First Search (BFS) Visualizer
Interactive breadth-first search on a grid — draw walls, move start/goal, generate mazes, step through the level-by-level expansion. Runs in your browser.
Open toolDepth-First Search (DFS) Visualizer
Interactive depth-first search on a grid — draw walls, move start/goal, generate mazes, step through the deep-dive exploration. Runs in your browser.
Open toolBubble Sort Visualizer
Animated bubble sort with step controls, speed, custom input, live comparison/swap counters and pseudocode. Runs entirely in your browser.
Open toolBuild, share, and grow on Zerethon Social
Free signup. Earn points, collect achievements, and connect with creators worldwide.