Browser Circuit Simulator and Schematic Editor
A browser-based electronic circuit simulator with drag-and-drop components, a wire tool, and real-time voltage, current and power readouts. Build circuits with batteries, resistors, potentiometers, LEDs, diodes, capacitors, inductors, transistors, switches, fuses, lamps, buzzers and motors, rotate and delete parts individually, connect them with wires and run a DC analysis — or drive it with AC and read the waveform on the built-in oscilloscope. Load example circuits or create your own — the simulation runs right in your browser.
How to Use the Circuit Simulator
Tap a component in the palette to drop it on the canvas. Select it to edit its properties and to rotate, copy or delete it right in place.
Drag from one component terminal to another to draw a wire, or switch to the Wire tool and tap two terminals. A wrong wire can be removed on its own: tap it and press the trash button.
Press Simulate to run the DC analysis. Voltage, current and power are shown on each component, current flow is animated through the wires, and overloads are flagged with clear warnings.
Design and simulate electronic circuits with an interactive drag-and-drop editor
What you can build here
Twenty-eight parts, and the solver knows the physics of each. Here is the full set, so you can tell before opening the canvas whether your circuit fits.
| Family | Parts |
|---|---|
| Power | Battery · AC source · Current source · Transformer |
| Passive | Resistor · Potentiometer · Capacitor · Inductor · Fuse |
| Sensors | Photoresistor · Thermistor |
| Semiconductors | Diode · Diode bridge · LED · Transistor · MOSFET |
| Switching | Switch · Button · Relay |
| Chips | Op-amp · 555 timer · Logic gate · NOT · Smart block |
| Loads | Lamp · Motor · Buzzer |
| Reference point | Ground |
How the circuit is solved
- The solve is DC steady state: a capacitor is an open circuit there and shows its settled voltage, an inductor is a short and shows its current. Time-varying sources are handled by a separate step-by-step run.
- The transistor is modeled as a switch: it opens at Vbe ≥ 0.7 V and holds Vce ≈ 0.2 V. There is no linear gain in the model — a deliberate simplification, so amplifier gain cannot be measured here.
- By default the numbers are life-like: a battery carries 0.5 Ω of internal resistance, so a 20 mA LED reads about 18.7 mA. Switch to the ideal model and the same circuit gives exactly the textbook 20 mA.
