NodeSim is the modern, free alternative to NI Multisim. Design, build, and run professional SPICE circuit simulations entirely in your browser. Whether you are an electronics engineering student, a hobbyist, or a professional hardware engineer, NodeSim provides a robust and accessible platform for all your circuit design needs. Say goodbye to complicated installations, expensive license headaches, and heavy desktop software. Just open your browser and start simulating instantly.
Under the hood, NodeSim is powered by an industry-standard ngspice engine compiled to WebAssembly (WASM). This means you get the exact same highly accurate mathematical models and simulation results you would expect from legacy desktop applications, but running entirely on the client side. Your schematics and data never have to leave your machine, ensuring complete privacy and lightning-fast simulation times with zero server latency.
NodeSim features an intuitive, drag-and-drop schematic editor designed for speed and simplicity. You can perform complex electronic analyses with just a few clicks:
Choose from an expansive library of over 311+ interactive components: microcontrollers (ATtiny85, PIC16F, STM32 Blue Pill, ESP32, Raspberry Pi Pico), 74HC & CD4000 CMOS logic gates, precision audio and instrumentation op-amps (TL082, NE5532, OP07, AD823, OPA134), optocouplers (4N25, 6N137, MOC3021), graphics displays (SSD1306 OLED, ILI9341 TFT, LCD1602 I2C), power MOSFETs, BJTs, diodes, and passive RLC components.
One of the biggest challenges in electronics education is troubleshooting. That's why NodeSim includes a built-in AI Engineering Tutor powered by Google Gemini, which can explain complex circuit behaviors and help debug wiring issues. Additionally, sharing your work has never been easier. You can generate a unique shareable link, export academic PDF lab reports with complete waveform plots, or embed your interactive circuit directly into a webpage.
Check out our extensive library of pre-built circuit templates, ranging from simple resistor networks and low-pass filters to complex operational amplifier circuits and 555 timers. Join the growing community of makers and engineers who are switching to the web's best free circuit simulator.