AlgorithmsSortingRuns in your browserReviewed October 1, 2026

Insertion Sort Visualizer

Grow a sorted section by sliding each new value left into its correct place. Interactive step-by-step animation with JavaScript code, complexity and front-end use cases.

Localprivate by defaultFastno sign-up path

SortingTime: O(n²), O(n) when almost sortedSpace: O(1)

Numbers (2 to 30, comma separated)

Step 1 / 61

The left part is treated as sorted. Each new value is slid left until it sits in the right place.

comparing
swapped / moved
pivot / minimum
sorted

JavaScript

1function insertionSort(arr) {
2  for (let i = 1; i < arr.length; i++) {
3    let j = i;
4    while (j > 0 && arr[j - 1] > arr[j]) {
5      [arr[j - 1], arr[j]] = [arr[j], arr[j - 1]];
6      j--;
7    }
8  }
9  return arr;
10}

Tip: use the arrow keys to step and the space bar to play or pause.

Loading animation...

Insertion Sort Visualization and Animation

Grow a sorted section by sliding each new value left into its correct place. Treat the first value as a sorted list of one. Take the next value and slide it left while the neighbour is bigger. Repeat until every value has been inserted. Time complexity: O(n²), O(n) when almost sorted. Space complexity: O(1). Fast on small or nearly sorted lists, which is why engines use it inside their built-in sort for short arrays.

How to use Insertion Sort Visualizer

Treat the first value as a sorted list of one.
Take the next value and slide it left while the neighbour is bigger.
Repeat until every value has been inserted.
Press Play, or step through with the arrow buttons and change the input to see how it reacts.

Questions

What is Insertion Sort?

Grow a sorted section by sliding each new value left into its correct place.

What is the time complexity of Insertion Sort?

Time: O(n²), O(n) when almost sorted. Space: O(1).

Where do front-end developers use Insertion Sort?

Fast on small or nearly sorted lists, which is why engines use it inside their built-in sort for short arrays.

Does this upload my data?

No. This converter runs in your browser for ordinary use, so the input is not sent to a backend by this tool.

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