Zen Circuit Lab vs Wokwi
Wokwi is the better place to run firmware. Zen Circuit Lab is the better place to see what the hardware around the firmware does, especially power. Bring a Wokwi project over to check its circuit.
Facts about Wokwi are from its public pages and documentation at the time of writing; tell us if something is out of date. Nothing here is a ranking: the two tools are for different jobs.
Side by side
| Zen Circuit Lab | Wokwi | |
|---|---|---|
| Price | Free, no account needed (an account only keeps progress across devices) | Free tier; paid Club for private projects and extras |
| Runs on | Browser, desktop or laptop; lessons work on a phone | Browser, VS Code extension, CI |
| Simulation | Electrical solver (modified nodal analysis) for analog and digital: every voltage and current, parts that heat, trip and burn | Simulates the firmware itself (compiled binaries for ESP32, AVR, RP2040, STM32); the electrical side is simplified, not an analog solver |
| View | 2D bench with a schematic view; 3D view of the bench, breadboard and perfboard | 2D diagram with realistic part drawings |
| Breadboard | Yes | Yes |
| Parts | 293 parts modelled on real products, each with a datasheet card | Sensors, displays, LEDs, buttons, motors, relays; a growing library with custom chips |
| Microcontrollers | ESP32 (WROOM, S3), Arduino Uno and Nano, Raspberry Pi Pico 2, LILYGO T-SIM: Arduino C++ sketches run by the lab's own compiler (not cycle-accurate firmware) | ESP32 family, Arduino Uno/Mega/Nano, Raspberry Pi Pico, STM32, with real firmware and Wi-Fi |
| Analog solver | Yes | Partly |
| Solar | Panels, PWM and MPPT controllers modelled on EPEVER, Renogy and Victron, inverters | No |
| Batteries and BMS | Cells and packs with real capacity and curves; BMS boards modelled on real products | No |
| Instruments | Multimeter, clamp meter, oscilloscope, function generator, LCR meter, electronic load, logic analyser | Logic analyser, serial monitor |
| Perfboard and PCB | Perfboard and PCB layout and routing, run on the same solver | No |
| House wiring | House wiring with breakers, RCD, outlets, appliances | No |
| Learning | 193 lessons, 7 courses, 66 guided builds with test sheets | Examples and documentation |
| Sharing and import | Share links; import Falstad, Wokwi and SPICE; export SPICE | Share links; projects as JSON |
| Source | Not open source | Simulator core partly open source |
Where Wokwi is better
- Cycle-accurate firmware: your real compiled binary runs, with Wi-Fi, FreeRTOS and the real peripherals.
- The widest set of boards and the best code tooling: VS Code, CI, debugging.
- A large library of sensors and displays and a big community.
Where Zen Circuit Lab is better
- The electrical side: an analog solver for the whole circuit, so power rails sag, dividers measure wrong and motors draw what they draw.
- Power: batteries with capacity and BMS, solar, chargers, converters; a board that browns out when the cell is flat.
- Courses, lessons and test sheets. Wokwi diagrams import onto the bench.
Open Zen Circuit LabFree, in your browser, no account needed.