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Land your
dream job
in data science

Practice real SQL and Python interview questions from top tech companies. Write code, run it instantly in your browser, and track your progress.

350+
Problems
3 Languages
SQL, Python & ML
100%
In-browser

Prepare for interviews at

Google Meta Stripe Amazon Apple Netflix

How it works

Three steps to interview-ready

1

Pick a problem

Browse questions by topic, difficulty, and language. Filter for SQL joins, Python pandas, window functions, and more.

2

Write & run code

Solve problems in our in-browser editor. Your code runs instantly — Python via WebAssembly, SQL against real databases. No setup needed.

3

Track & improve

See which topics you've mastered and where you need practice. Your dashboard shows progress by difficulty and topic area.

Built for data scientists

Purpose-built for
data science interviews

Generic coding platforms don't prepare you for data science interviews. Our questions are written by someone with a PhD in Machine Learning who has been on both sides of the interview table.

Real SQL on real databases

Write queries against actual tables with real data. JOINs, CTEs, window functions — the stuff interviewers actually ask.

Python with pandas & numpy

Full Python runtime in your browser via WebAssembly. Import pandas, numpy, and scikit-learn — no installation required.

Statistics & ML questions

Beyond syntax — correlation, feature engineering, KNN implementation. The conceptual questions that separate good from great candidates.

The platform

Everything you need to prepare

Professional Code Editor

Split-pane IDE with syntax highlighting, auto-formatting, and keyboard shortcuts. Run and submit with Ctrl+Enter.

Visible & Hidden Test Cases

See sample test cases to build your solution, then submit to run against hidden tests. Per-test pass/fail feedback shows exactly where you stand.

Step-by-Step Explanations

Every problem includes a detailed walkthrough covering approach, key concepts, complexity analysis, and common pitfalls.

Company-Tagged Questions

Filter by Netflix, Airbnb, Google, and more. Practice the exact types of questions asked at your target company.

Progressive Hints

Stuck? Reveal hints one at a time to nudge you in the right direction without giving away the answer.

Progress Dashboard

Track your progress with an engagement heatmap, difficulty breakdown, and recent submissions. See exactly where to focus.

Why it's worth it

The ROI is obvious

Data science is one of the highest-paying fields in tech. At $20/mo, you're investing less than a lunch to land a six-figure career.

$130k

Median US salary

Data scientists, Bureau of Labor Statistics

$175k+

Top tech companies

Average base at FAANG and major tech firms

$250k+

Senior-level TC

Total compensation for senior data scientists

#1

Fastest-growing field

Top career in tech for growth and demand

Simple pricing

Invest in your career

Start free, upgrade when you're serious. The average data science salary is $150k+ — this pays for itself on day one.

Monthly Yearly Save 38%

Free

Try before you commit

$0 /forever
  • 5 free problems (SQL + Python)
  • In-browser code execution
  • Basic progress tracking
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Pro

Full access to everything

$20 /month $149 /year
  • All 350+ problems (growing weekly)
  • Step-by-step explanations
  • Company-tagged questions
  • Full progress dashboard & heatmap
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1:1 Coaching

Guaranteed results

$2,500 one-time
  • Everything in Pro
  • 8 private coaching sessions
  • Personalized study plan
  • Mock interviews with feedback
  • Direct access via Slack
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