Mokxi is a free Wokwi alternative for Arduino, ESP32, Pico and STM32 boards that runs in your browser. It compiles your sketch in the tab with no build server, solves the analog parts of a circuit, and wraps the simulator in a full class workflow. Wokwi is an excellent browser simulator for makers, with a wide range of ESP32 chips, the Arduino Library Manager, MicroPython and mature developer tooling. Mokxi pairs real firmware simulation and bench instruments with analog circuits and a complete teacher workflow. Here is where each one is the right answer.
Last checked October 2026
The Mokxi editor running an ESP32-C3 that drives a 16 by 16 WS2812 LED panel, with the sketch open beside the wired board.
These are the strongest reasons to choose Wokwi today.
These are working parts of Mokxi you can open and test for yourself.
Each one links to the request on Wokwi’s own public tracker and to a Mokxi page where you can run the answer. None of this is a criticism of Wokwi; every tool has a list like this.
Wokwi builds sketches on its servers. On the free plan, users have reported long waits and “Build server busy” errors on its issue tracker since at least 2025. Mokxi compiles in your own tab, so a build never waits behind anyone else’s. We have not measured Wokwi; our own times are measured on /fast.
Their request
See it in Mokxi
A request to simulate resistor dividers has been open on Wokwi’s tracker since October 2021, and one for transistors since 2021. Mokxi solves the analog parts of a circuit with real device models: Shockley diodes and LEDs, Gummel-Poon transistors on their vendors’ own cards, an op-amp macromodel, with DC sweeps and Bode plots.
Their request
Simulating several MCUs in one diagram has been an open request on Wokwi’s tracker since 2021, with 31 reactions. In Mokxi a project can hold several boards, each with its own sketch, and the wires between them carry real signals.
Last checked October 2026. If anything here has gone stale, that is our mistake and we want to know.
| Mokxi | Wokwi | |
|---|---|---|
| Best fit | Teacher-led electronics classes and breadboard work | Maker projects and firmware experiments |
| Boards | 32 Arduino, ESP32, ESP8266, Pico, STM32, micro:bit and ATtiny85 boards | Arduino, many ESP32 chips, STM32, Pico and ATtiny85 |
| Compiling | In the browser tab, with no build server, queue or build minutes | On Wokwi’s build servers; paid plans add monthly fast build minutes |
| Boards in one simulation | Several, each with its own sketch | One microcontroller per simulation; multiple MCUs is an open feature request |
| Libraries | More than 100 common Arduino libraries built in, as Mokxi’s own headers; libraries of your own on every plan | The Arduino Library Manager on every plan; libraries of your own on paid plans |
| Languages | Arduino C++ | Arduino, ESP-IDF, MicroPython, CircuitPython and Rust |
| Analog circuits | Nodal analysis with real device models, sweeps and Bode plots, and SPICE decks | Digital simulation; analog simulation of a resistor divider is an open feature request, and users on the Arduino Forum note that analog circuits do not simulate |
| Class workflow | Roster, starters, live wall, checks, submissions, feedback and gradebook CSV | A classroom license |
| Debugging | Source steps, breakpoints, registers, watches and a 4-channel protocol-decoding analyzer | GDB in the browser, an 8-channel analyzer, and VS Code on paid plans |
| Networking | A simulated network for HTTP lessons, contained in the browser, with an editable JSON API and a full request log | Simulated WiFi with internet access, HTTP and MQTT, and a private IoT gateway on paid plans |
| Price | Free; paid plans add room and class tools | A free Community plan; paid Hobby, Hobby+ and Pro plans |
Sources for Wokwi
Straight answers. Where the other one is the right call, we say so.
Wokwi. Those are among its clearest strengths today.
Wokwi. Mokxi runs Arduino C++ only.
Wokwi takes any library in the Arduino Library Manager, on its free plan. On Mokxi you can add a library yourself, as a zip or as .h and .cpp files, on every plan.
Mokxi. The class workflow is built around that job.
Mokxi. A divider, an RC filter or a button ladder on one analog pin reads the voltage the parts set.
Wokwi, on its Hobby+ and Pro plans. Mokxi’s extension keeps the sketch in VS Code and runs it in the browser or through the API.
Mokxi.
Mokxi. Each board runs its own sketch, and the wires between them carry real signals.
Mokxi compiles in your own browser, so there is no queue. Wokwi’s paid plans add fast build minutes if you would rather stay.
Wokwi is very good at what it does, and for many makers the honest answer is to keep using it. The people who look for an alternative are usually teachers who need a class workflow around the simulator, learners who want a real breadboard and bench instruments next to the code, or someone whose circuit has analog parts that have to behave like the analog parts on a bench. Both tools run a simulation without an account, so that is not a reason to move either way.
Mokxi is built around those needs: a 0.1 inch breadboard with rails and a center channel, an oscilloscope, a logic analyzer with UART, I2C and SPI decoding, a multimeter and a bench supply as parts you wire in, a source debugger, and a class workflow with starters, checks, submissions and a gradebook. The compiler runs in your own browser, so a build never waits on a server. The free plan has every board and every part, and the editor opens and runs without an account.
Moving a project over takes one step: paste its Wokwi link, or drop its diagram.json and sketch or its zip, on the import page. The parts, their wiring, the sketch and its tabs come across, a part plugged into a Wokwi breadboard lands in the same holes, and a report lists what did not map and which libraries are built in or missing. Standard Arduino calls and the common library headers compile as they are. Wokwi’s MQTT broker access and custom chips have no equivalent in Mokxi today, and neither do MicroPython or ESP-IDF, so a project built on those should stay where it is. Going back is as easy: the editor’s Export menu writes a Wokwi project zip, diagram.json, sketch.ino and libraries.txt, with a README naming anything Wokwi has no part for.
The same straight comparison for the tools teachers, students and makers also consider.
Mokxi runs eleven ESP32 boards on its free plan, from the classic ESP32 DevKit and the ESP32-S3 to the ESP32-C3 and C6, plus three ESP8266 boards, with a simulated WiFi network for HTTP lessons. Wokwi covers a wider range of ESP32 chips and features, including MQTT and MicroPython.
Yes. The import page takes a public Wokwi project link, or the project’s diagram.json, sketch and libraries.txt, or its zip, and opens it in the editor with a report of what came across. Parts Mokxi does not have yet become labeled notes on the canvas. Arduino IDE sketches import the same way.
Yes. The Mokxi extension for VS Code lists your projects, opens a sketch as an Arduino IDE folder, syncs your edits and runs the project on Mokxi’s servers with the serial output in a VS Code panel. The same files work with the mokxi command line tool. The simulation itself runs in the browser or through the API, not inside VS Code.
No. A real clang and lld, compiled to WebAssembly, build the sketch in your browser, so there is no build server and no queue. The first build in a fresh browser downloads the compiler once; after that only your sketch is compiled. The /fast page has the measured times and the script that measures them.
Wokwi. Those are among its clearest strengths today.
Wokwi. Mokxi runs Arduino C++ only.
Wokwi takes any library in the Arduino Library Manager, on its free plan. On Mokxi you can add a library yourself, as a zip or as .h and .cpp files, on every plan.
Mokxi. The class workflow is built around that job.
Mokxi. A divider, an RC filter or a button ladder on one analog pin reads the voltage the parts set.
Wokwi, on its Hobby+ and Pro plans. Mokxi’s extension keeps the sketch in VS Code and runs it in the browser or through the API.
Mokxi.
Mokxi. Each board runs its own sketch, and the wires between them carry real signals.
Mokxi compiles in your own browser, so there is no queue. Wokwi’s paid plans add fast build minutes if you would rather stay.
A comparison page is somebody else’s opinion. Open the editor, press Run and make up your own mind.