Understand before you memorize.

OhmPlay is a free electronics, control and robotics lab made in Mexico that runs in your browser. It's for students, teachers, hobbyists and makers who want to see what happens in a circuit, not just learn the formula.

The name joins two ideas: the ohm, the unit of resistance and the first law anyone learns in electronics, and play, because here you learn by changing values and trying things out.

What you'll find

Tools for electronics, digital logic, control and robotics: change a value and see the result, the circuit and the formula at the same time.
Guides with worked examples and the most common mistakes.
Guided experiments: predict what will happen, change a value and check whether you were right.

No account and no installation needed. Everything is calculated in your browser.

How we make sure the calculations are right

Every tool is tested against known cases before it's published, and checked with independent calculations. When a model simplifies reality (ideal components, no tolerances or temperature), we say so next to the result. The explanations and exercises are written for this site.

We have no certifications or agreements with educational institutions, and we don't claim endorsements that don't exist.

How the site is funded

OhmPlay is free. To support it, the site shows or may show Google AdSense ads. The details are in the privacy notice and the legal notice.

Write to us

Found a calculation error, something unclear, or want another tool? Email us at [email protected], or see what's useful to tell us.