Draw a Zero and See a Neural Network Prediction

The useful part

Keras.js is featured here for one specific job: pretrained MNIST digit prediction with visible feature maps. This guide focuses on that workflow so you can decide whether it fits your task before trying it.

What happened in the demo

Open Keras.js and draw one oval zero in its digit canvas. This free browser demo uses a pretrained model. Here’s the recorded result: it predicts zero. Those little grids are feature maps, showing intermediate activity inside the network. It’s a hands-on way to explore a digit prediction, right in your browser.

The example used in the reel

A small, specific input makes the result easier to inspect. Use the example below to understand the scope of the recorded workflow; it is not a promise that a new run will produce an identical result.

Draw one oval zero in the public Basic Convnet for MNIST canvas, then inspect the digit output and feature maps.

Try it yourself

1. Draw a zero in the digit canvas
2. Read the model's prediction
3. Try a small change and compare the output

Start with material you own or have permission to use. Save the original and compare it with the output before moving the result into a real project. If the interface has changed, follow the current official instructions linked below.

What to check before using the result

One correct digit does not measure general accuracy. Handwriting and stroke thickness can affect the result.

Keep the task narrow on your first attempt. Check the details that matter to your use case rather than judging only whether the result looks polished. A successful short example is a useful introduction, not a benchmark of the whole product.

Access, free demos & limits

The recorded browser demo required no payment, account, installation or upload. Its official repository says the demos still work, but the project is no longer maintained. The demo URL was reachable on 2026-10-26.

Availability notes refer to the dated demonstration or source check. Features, limits and sign-in requirements can change. Check the official site before starting a larger project.

Sources & context

• transcranial.github.io/keras-js/ ↗Source checked 2026-10-26
• github.com/transcranial/keras-js ↗Source checked 2026-10-26

This guide expands the channel’s recorded example and the official sources checked for that reel. Generated results are examples, not endorsements or guarantees. Read our editorial policy.