About FreeCircuitSim

FreeCircuitSim is a free, browser-based electronic circuit simulator and learning platform. Our goal is simple: make circuit simulation and electronics education available to anyone, on any device, with zero cost, zero downloads and zero accounts — forever.

What this site offers

• A real-time interactive circuit simulator with 50+ component types and animated current flow
• 360+ ready-to-run example circuits, loadable in one click
• 24 written guides and 7 step-by-step guided simulations, from complete beginner to op-amps and power converters
• An AI circuit explainer that turns any circuit description into plain English

The simulation engine

The simulator is built on CircuitJS1, the open-source engine originally created by Paul Falstad and ported to the browser by Iain Sharp, released under the GPL v2 licence. We host our own compiled build and add the guides, examples library, and learning tools around it. Full credit belongs to the CircuitJS1 authors and community.

Who runs it

FreeCircuitSim is independently operated from Sydney, Australia. The site is supported by advertising and affiliate links, which is what keeps the simulator and every guide free for everyone.

Independence

FreeCircuitSim is not affiliated with, endorsed by, or connected to National Instruments (Multisim), Analog Devices (LTspice), Elsewhere Labs (CircuitSim®), Autodesk (Tinkercad) or any other simulation vendor mentioned in our comparison guides. All trademarks are the property of their respective owners and are referenced only to identify the products being compared.

Questions or suggestions? Get in touch here.