Is this circuit simulator free to use?

Yes. The browser-based circuit simulator is free to start and designed as a learning companion for electricians, students, and DIY users.

Can I use it for electrician exam practice?

Yes. It helps visualize common circuit concepts such as loops, switches, loads, current flow, and basic fault conditions used in electrical training.

Does it replace professional electrical design software?

No. It is intended for education and planning. Real installations must follow local electrical codes and be reviewed by qualified professionals.

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Interactive circuit lab

Circuit Simulator

Build and test virtual circuits

Run your first circuit in 30 seconds

Create a battery, switch, lamp, and wires in one click. Press Run to see current flow and lamp status.

Load a complete starter circuit

Press Run to view current and lamp output

Click the switch to toggle ON/OFF; drag parts and wires follow

Save circuit project

Free includes 5 saves/month. Pro/Lifetime saves are unlimited.

Mobile optimized: use Canvas first, Tools to add parts, Diagnostics for results. Dragging inside the canvas will not scroll the page.

Components

SOURCE / PASSIVE

电源与基础无源元件

CONTROL / LOAD

开关、控制与负载

PROTECTION

保护与配电元件

Measuring Tools

Ready to test: click Run to inspect the circuit

Click Run to watch current flow and diagnostics.

Why this happens

Simulation has not started yet. After running, the tool checks current flow, load status, and safety risks.

What to do next

Add a battery or AC source first.
Add a lamp, resistor, or motor as the load.
Use Run demo if you want a complete starter circuit.

Circuit diagnostics

Circuit diagnostic summary

Not running

Total current

—

Total power

—

Loop

Not running

Live objects

0 components / 0 wires

Fault locations

Run the circuit to list locatable problem points here.

Run effects

Run the circuit to explain lamps, switches, and protection devices.

Load details

Click Run to show load parameters.

Terminals glow on hover; drag from one terminal to another to wire. Press Esc to cancel wiring.

Wire selected: drag either endpoint to reconnect; press Delete to delete.

Dragged parts are highlighted; connected wires stay attached after release.

Switches show ON/OFF. Click the switch body to toggle.

• Click to select, then click another to connect

• Click switch again to toggle ON/OFF

• Switch must be ON to conduct current

• Double-click component to edit parameters

• Select a wire, then click Delete wire or press Delete/Backspace.

STOPPED

Touch mode: tap parts/wires; drag terminals to wire or reconnect.

Oscilloscope / Live traces

Voltage trace preview derived from current solver values

rest f = —