PPolySim OS

k-Means Clustering

The workhorse of unsupervised learning. Watch centroids drift into place as k-means discovers the clusters hidden in unlabeled data.

k-Means ClusteringLive

Controls

Presets

Lloyd's algorithm: assign each point to its nearest centroid, then move each centroid to the mean of its members. Repeat until stable. Try setting k different from the true cluster count.

▶ Run in Python

Data Inspector

Iteration0
Inertia0.00e+0
k4

Governing equation

Reading this result: k matches the 4 true clusters, so each centroid can settle onto one real group and inertia falls to a clean minimum.

Runs locally in your browser — free forever. Scale to the cloud when reality gets heavy.

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How it works

k-means alternates two steps: assign every point to its nearest centroid, then move each centroid to the average of its assigned points. Repeating drives down the within-cluster variance (inertia) until it converges. Try setting k different from the true number of clusters to see how the choice matters.

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Frequently asked questions

Is this k-means clustering tool really free?
Yes. k-Means Clustering runs entirely in your browser using your device's own compute, so local use is free forever. You only pay Compute Tokens if you scale a job to the cloud.
Do I need to install anything?
No. Everything runs client-side in a modern browser — no downloads, no license, no account required to start.
Can I save or share my simulation?
Create a free account to save projects, and use a shareable embed or minted DOI to publish a live, interactive version anywhere.
How accurate are the results?
The solver uses established numerical methods, but results are for research and educational purposes and should be validated against experiment or professional review before you rely on them.