Build real circuits in your browser.
TinyOhms is a breadboard simulator for people who have never built a circuit, and a library of projects that show the math behind every part. Build it on screen first. Then build it for real.
Also on iPhone and iPad — the free TinyOhms app is the same breadboard, offline.
simulating…
the workbench
Every part, live.
Batteries, resistors, LEDs, capacitors, transistors, a 555 timer. Place them on a breadboard and the circuit runs as you build. Skip the resistor and the LED pops. Checked against ngspice.
the projects
Understand, don't follow.
Every project shows the actual numbers — why 220 Ω, why 11 mA — and ends with a challenge that has more than one right answer. Each one opens in the Workbench before you touch a wire.
the ladder
Nothing gets binned.
Ten levels, from Light to Connected. Each adds a few real components, and every project can use everything you already own.
Start tonight
Three Level 1 projects, fully worked. No parts needed to try them on screen.
First Light
Build a real flashlight circuit and learn why every circuit is a loop.
Tabletop Traffic Light
Three LEDs on three parallel lanes, all lit by one switch — build a tabletop traffic light and discover parallel circuits.
Morse Code Messenger
A push button, an LED, and a secret code — send real messages with light.