TeachCode — Learn to code by writing code — Python, SQL and JavaScript, right in your browser.
TeachCode is a full coding platform — 114 units and 649 hands-on exercises across Python, SQL and JavaScript. Go from your first program to pandas, machine learning and deep learning, and from SQL joins to window functions and business analysis. Every exercise runs and is checked on your own device — no setup, nothing to install.
What you get
649 hands-on exercises
Across Python (425), SQL (204) and JavaScript (20) — each one checked by actually running your code, not a multiple-choice guess.
Runs in your browser
Python runs through Pyodide and SQL through sql.js, in a sandbox on your own device — nothing to install, nothing sent to a server.
From basics to machine learning
NumPy, pandas, charts, statistics and BI — then scikit-learn, XGBoost and deep learning built from first principles.
SQL on real databases
Joins, subqueries, window functions and CTEs across five practice databases — up to real business analysis.
Practise on your own data
Load a CSV, Excel file or Google Sheet — or connect your own Supabase or Appwrite tables — and analyse it live in the Playground.
How it works
- 1
Pick a track — Python, SQL or JavaScript
- 2
Read the short lesson, then open the example in the Playground
- 3
Solve exercises that run and auto-check on your device
- 4
Clear units to level up — or bring your own data