Code, build and practice — right in your browser
A real Python compiler, a live HTML/CSS/JavaScript editor and an Arduino simulator — plus practice questions that are checked the moment you press a button. Made for NIELIT O Level students.
- Free tools
- 3
- Free tools
- Question types
- 57
- Question types
- Installs needed
- 0
- Installs needed
- Always free
- ₹0
- Always free
Run real Python in a second
Online Python Compiler
Not a simulation — the same Python 3 your computer runs, with input() and NumPy. Load an example, change it, and see the output instantly.
- input() support with a separate input box
- NumPy arrays and matrices
- Endless loops are stopped safely after 15 seconds
Build a web page and watch it appear
HTML, CSS & JavaScript Editor
HTML, CSS and JavaScript side by side with a live preview that updates as you type. Download the finished page as one file.
- Tables, forms, lists and Flexbox examples
- JavaScript runs safely in a sandbox
- Download as a single .html file
Blink an LED without owning a board
Arduino Simulator
A virtual Arduino Uno opens right on the page. Pick a ready sketch with its wiring, paste it in and press play.
- LED, button, PWM, sensors, LCD and servo sketches
- Exact wiring for every sketch
- Free simulator, no account needed
Every program, explained
The code, the output, how it works step by step and the mistakes to avoid — with a Try it Yourself button on every one.
How it works
Pick a tool
Python, HTML/CSS/JS or Arduino — whichever your module needs.
Write your code
A big editor with examples to start from. Everything runs in your browser.
Check it instantly
Run it, or take a practice question and get it marked in seconds.
Why students use these tools
Runs in your browser
Real Python, a live web preview and a virtual Arduino — no software to install.
No login, no fee
Open and start. Your code stays on your device and is never uploaded.
Works on your phone
Built mobile-first, so you can practice on the bus or at home.
Share on WhatsApp
One tap sends your program to a friend or teacher — it opens with your code in it.
A new question every time
Practice questions are generated fresh with new values, so they never run out.
Made for NIELIT O Level
Mapped to M2, M3 and M4 and the PR-2, PR-3 and PR-4 practical exams.
Which tool should I use?
Python Compiler — for NIELIT O Level M3 (Programming and Problem Solving through Python) and the PR-3 practical. It runs real Python 3, supports input() and includes NumPy.
HTML, CSS & JavaScript Editor — for O Level M2 (Web Designing and Publishing) and the PR-2 practical: tables, forms, lists, CSS styling and small JavaScript programs, with a live preview.
Arduino Simulator — for O Level M4 (Internet of Things) and the PR-4 practical: LEDs, buttons, PWM, sensors, LCD and servo motors on a virtual Arduino Uno.
Each tool also has practice questions — a new one every time, checked automatically. When you are ready, attempt a timed O Level practical mock test.
Want to learn this properly?
Zed-King Institute, Kaithal is a NIELIT Study Centre. Join the O Level course for guided classes, lab practice and full exam preparation.