Free labs and tools, in your browser.
Real code, real models and real documents, free and with no sign-up. The labs run on your device, so your work stays with you. A step-by-step path through them is on Learn.
Practise with real code
- SQL Lab40 interview questions on real PostgreSQL, checked as you go.Downloads about 5 MB the first time
- Python Lab35 questions in real Python with pandas and NumPy.About 6 MB the first time, 8 MB more for pandas
- ML Lab40 machine learning questions with real scikit-learn and its charts.Downloads about 32 MB the first time
Practise with Prism
- Interview practiceAnswer 5 questions for your role; Prism shows what you covered and what to add.Verify your WhatsApp number once
- Resume checkPrism reads your resume for a role and suggests what to fix. Nothing of it is kept.Verify your WhatsApp number once
See how AI works
- Token counterHow many tokens your text takes on GPT-5, Gemini and Sarvam, in Hindi or English.Nothing to download for the samples
- Temperature playgroundMove temperature, top-k and top-p on a real model’s chances.Nothing to download
- RAG chunkingCut a real document and see what a search by meaning and by keywords finds.Nothing to download
See the statistics and machine learning
- Confusion matrixMove a real churn model’s line and watch precision, recall and the ROC curve.Nothing to download
- OverfittingFit a curve of degree 0 to 15 and watch its error on new points fall, then soar.Nothing to download
- A/B test calculatorHow many visitors a test needs, whether a result is significant, and why peeking misleads.Nothing to download
- Central limit theoremWatch averages of any shape turn into a bell, and what 95% confidence means.Nothing to download
- Neural networkTrain a small network on XOR, a circle or a spiral, and watch it learn.Nothing to download