The world's first free 3D circuit simulator in your browser.

Build real circuits with components. Powered by nodal analysis physics. No download. No account required to start.

Components
Real MNA Physics
100% Free, Forever

Everything you need to build.

Professional-grade tools wrapped in an intuitive, game-like 3D interface.

True 3D

Orbit, zoom, and drag components on a real 3D workbench. Every component is a detailed 3D model — not a flat schematic symbol.

Real physics engine

Modified Nodal Analysis (MNA) solver — the same method used by SPICE. Parallel paths, voltage dividers, and multi-source circuits all solved correctly.

Components

From basics like resistors and LEDs to transistors, logic gates, relays, and RGB LEDs. Every component has accurate DC simulation behavior.

AI circuit assistant

Ask CircuitForge AI why your LED isn't lighting up. Powered by Gemini — responses stream back fast and smart.

Save & share

Sign in with Google to save unlimited circuits. Share any circuit with a public link — one click, anyone can load and explore it.

15 starter templates

Load a working circuit instantly: LED + resistor, voltage divider, H-bridge, transistor switch, logic gates, and more.

How it works

1

Pick a component

Click the sidebar, place it on the 3D board.

2

Wire it up

Connect pins with the wire tool.

3

Hit RUN

MNA solver shows live voltage and current on every component.

Components and counting

Battery
Resistor
LED
Switch
Capacitor
Bulb
Diode
Inductor
Motor
Buzzer
Voltmeter
Ammeter
Potentiometer
NPN Transistor
Transformer
Fuse
Solar Panel
AND Gate
OR Gate
RGB LED
Zener Diode
Relay

Students

Build circuits for physics class without buying components. Understand Ohm's Law and Kirchhoff's laws visually.

Hobbyists & Makers

Prototype your Arduino or ESP32 circuit before soldering. Test LED arrays, motor drivers, and sensor circuits instantly.

Engineers & Educators

Demonstrate circuit behavior to students in 3D. Share live circuit links in course materials.