The Playgrounds

Theory is great, but have you ever poked a neural network with a stick? New lab every Sunday.

Interactive Demo
LAB #3beginner

How LLMs Work: The Full Pipeline

Type a sentence and watch it flow through an LLM, tokenization, embeddings, attention, and prediction, step by step.

Launch Lab

All Labs

LAB #1intermediate

Understanding Backpropagation

Step through forward & backward passes interactively, watch gradients flow through every node.

8 minPlay
LAB #2beginner

The Blind Hiker, Gradient Descent Playground

Drag a ball on four different loss surfaces. Tune the learning rate. Trigger four built-in failure modes. Watch the loss curve go down, or explode.

5 minPlay
intermediate

Backpropagation Playground: Step Through a Neural Network

Step through forward pass, backward pass, and weight updates in a neural network or CNN, watching the math unfold at every step.

10-15 minPlay
intermediate

Interactive CNN Builder: Snap Together a Conv Net

Upload custom images and snap together CNN blocks dynamically to build your own feature extraction pipeline.

10-15 minPlay
beginner

CNN Layer Explorer: See What a Conv Net Sees

See what a CNN sees at every layer. Pass an image through a convolutional neural network and visualize feature maps, activations, and pooling.

5-10 minPlay
intermediate

Neural Network Digit Classifier: Draw and Classify

Draw digits on a canvas and watch a neural network classify them in real time, see activations flow through every layer.

5-10 minPlay
beginner

Linear Regression Visualizer: Fit a Line to Data

Drag data points and watch the best-fit line update in real time. See how linear regression minimizes error to find the line through your data.

5 minPlay
beginner

Logistic Regression Visualizer: Draw a Decision Boundary

Watch logistic regression separate two classes with a decision boundary. Add points and see the sigmoid curve and probabilities update live.

5 minPlay
beginner

Decision Tree Visualizer: Watch It Split Data

See how a decision tree splits data step by step. Watch it carve the feature space into regions and grow branches to classify points.

5-10 minPlay
intermediate

Random Forest Visualizer: Many Trees, One Vote

See how a random forest combines many decision trees into one prediction. Watch individual trees vote and the ensemble smooth out the boundary.

5-10 minPlay
beginner

K-Means Clustering Visualizer: Watch Clusters Form

Watch k-means clustering find groups in data. Step through centroid updates and assignment as the algorithm converges on clusters.

5-10 minPlay
intermediate

Overfitting Visualizer: Bias vs Variance, Live

See overfitting happen in real time. Crank up model complexity and watch the curve hug the noise instead of the signal, the classic bias-variance tradeoff.

5-10 minPlay
intermediate

Neural Network Visualizer: Watch a Net Learn

Watch a small neural network learn to separate data. See neurons, weights, and the decision boundary update as it trains in your browser.

5-10 minPlay
advanced

Recurrent Neural Network Visualizer: Sequences Step by Step

See how a recurrent neural network processes a sequence one step at a time, carrying hidden state forward. Watch memory flow through the unrolled network.

8-12 minPlay
advanced

Transformer Visualizer: See Attention Light Up

Watch a transformer attend across tokens. See attention weights light up token by token, the mechanism behind modern language models.

8-12 minPlay
advanced

GAN Visualizer: Generator vs Discriminator

Watch a generative adversarial network train. See the generator and discriminator fight it out as fake samples slowly start to look real.

8-12 minPlay
advanced

Reinforcement Learning Visualizer: Watch an Agent Learn

Watch a reinforcement learning agent learn by trial and error. See rewards shape its policy as it explores a grid world and finds the goal.

8-12 minPlay

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