# Velxio — Free Local Arduino Emulator | AVR8 · RP2040 · 48+ Components
Velxio is a free, open-source Arduino emulator that runs entirely in your browser. Real AVR8 emulation at 16 MHz, 48+ electronic components, Monaco Editor, Serial Monitor, and Library Manager — no cloud, no latency.
Author: David Montero Crespo
Keywords: arduino emulator, arduino simulator, avr8 emulator, avr simulator, rp2040 emulator, arduino online, wokwi alternative, arduino ide browser, arduino simulator free, attmega328p simulator, raspberry pi pico emulator, arduino uno simulator, electronics simulator, velxio

## The free, open-source Arduino emulator that runs in your browser

Write Arduino code, compile it, and simulate it with real AVR8 CPU emulation and 48+ interactive electronic components — all running locally in your browser. No cloud, no latency, no account required.

### Features

- Real ATmega328p (AVR8) emulation at 16 MHz via avr8js
- Raspberry Pi Pico (RP2040) emulation via rp2040js
- 48+ wokwi interactive electronic components (LEDs, resistors, buttons, sensors…)
- Monaco Code Editor with full C++ / Arduino syntax highlighting
- arduino-cli compilation backend — produces real .hex / .uf2 files
- Serial Monitor with auto baud-rate detection and send
- Library Manager for Arduino libraries
- Multi-file workspace (.ino, .h, .cpp)
- Wire system with orthogonal routing
- ILI9341 TFT display simulation
- I2C, SPI, USART, ADC, PWM support
- Docker standalone image — deploy anywhere with one command

### Supported Boards

- Arduino Uno (ATmega328p) — full AVR8 emulation
- Raspberry Pi Pico (RP2040) — RP2040 emulation

### Get Started

Open the Editor — no installation needed.
Self-host with Docker: `docker run -d -p 3080:80 ghcr.io/davidmonterocrespo24/velxio:master`

### Documentation

Browse the full Velxio documentation to learn how to set up, configure, and extend the emulator:

### Frequently Asked Questions

Is Velxio free?
  Yes. Velxio is free and open-source under the GNU AGPLv3 license. A commercial license is available for proprietary integrations.
Does Velxio work offline?
  The simulation engine runs entirely in the browser. Compilation requires the local arduino-cli backend. Self-hosted deployments work fully offline once running.
Is Velxio a Wokwi alternative?
  Yes. Velxio is a free, self-hosted alternative to Wokwi. It uses the same avr8js and wokwi-elements open-source libraries but runs on your own machine.
What boards are supported?
  Arduino Uno (ATmega328p / AVR8) and Raspberry Pi Pico (RP2040). More boards are planned.