PPolySim OS

Logistic Regression

Logistic regression is the workhorse of classification. Watch it bend a straight line into an S-curve that outputs a clean probability.

Logistic RegressionLive

Controls

Presets

Logistic regression squashes a linear score through the sigmoid to output a probability between 0 and 1. Predictions above the threshold become one class, below it the other. Raising the weight sharpens the S-curve into a harder decision. Educational tool.

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Data Inspector

Decision boundary at x0.50
P(class 1 | x=1)0.82
Threshold0.50

Governing equation

Reading this result: Logistic regression fits this sigmoid by gradient descent on cross-entropy. Weight w=3 sets steepness, bias b=-1.5 shifts the curve, placing the decision boundary at x=0.50 for threshold 0.5.

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

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How it works

Logistic regression computes a weighted score and passes it through the sigmoid to produce a probability between 0 and 1. A threshold turns that probability into a class. Despite the name it is a classifier, and it underpins everything from credit scoring to medical risk models. Educational tool.

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Frequently asked questions

Is this logistic regression simulator tool really free?
Yes. Logistic Regression 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.