Questions about the Rangkai Arduino simulator

Rangkai is a free online Arduino and electronics simulator that runs in your browser. Build circuits with LEDs, resistors, buttons, sensors, and dozens of other parts on a virtual breadboard, program them with blocks or C++ code, and watch the simulation run instantly.

Yes. Every part lives in the simulator, so you don't need to buy an Arduino board, breadboard, or wires first. The code you write is real Arduino code, so you can use it on a physical board later.

Free, with no ads. Rangkai runs in any modern browser on laptops, Chromebooks, tablets, and phones, with nothing to install. You can also try example projects without signing up.

Yes. There are four levels: Beginner and Basic use the block editor (Beginner with picture passwords for primary school), Intermediate uses C++ code, and Advanced is for projects with several files. You can switch levels any time.

Arduino Uno, Arduino Nano, Arduino Mega, and the ESP32-C3 SuperMini, plus breadboards, resistors, diodes, transistors, and batteries.

There are 59 components, including LEDs, RGB LEDs, LED bars, buttons, potentiometers, buzzers, servos, 7-segment displays, LCDs, keypads, ultrasonic distance sensors, temperature sensors, and gas sensors. Admins can choose the parts for each level, and teachers can limit parts per assignment.

Rangkai checks your circuit and explains problems in plain language, such as an LED without a resistor or an unconnected pin. A wrongly connected part can look burnt on screen, so you learn from mistakes without breaking anything real.

Yes. Programs are compiled with the official Arduino tools, so the code is ordinary Arduino C++. Programs made with blocks can be turned into text code too, then copied into the Arduino IDE to upload to a real board.

Yes. The Serial Monitor shows text from Serial.print, and the Serial Plotter draws charts from the numbers you send, such as sensor readings. There's also a pin view to help track down bugs.

Yes. Import a Wokwi diagram.json, optionally with sketch.ino and libraries.txt, from My projects. You'll be told about any parts that aren't supported yet.

Open Sign in, choose I'm a student, type the class code from your teacher, then pick your name (or I'm new in this class) and your password. Students don't need an email.

Ask your teacher. They can see the class code and reset your password from the class page.

In the editor, press the Instructions button (the checklist icon) next to Submit. The assignment instructions appear without leaving the canvas.

Teachers create a class, share the class code, and set assignments with a starter project and allowed parts. The Share assignment button prepares a ready-to-send WhatsApp message with the site address and class code.

Teachers save a finished result as the answer key. Student submissions are compared by their circuit connections and by how they behave when the program runs, including the order and timing of lights. Teachers can still adjust grades and leave comments.

Live quizzes are played together in class like an interactive quiz, with points for fast, correct answers. Circuit races are timed assignments where students compete to finish a working circuit first. Quiz results can be reviewed later from the history.

As little as possible: names, email for teachers and personal accounts, passwords as hashes, and projects and assignments. Students only need a nickname. Full details are in the privacy policy.

No. There are no ads and no tracking cookies. Visit statistics are counted in-house without cookies, and cookies are only used to keep you signed in.