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Walk into your data interview having already solved the hard ones.
Most of our practice library is free. Premium adds the harder company questions and the advanced portfolio projects that make a hiring manager stop scrolling, so you prepare for the interview you'll actually face.
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- 132 interview questions in SQL, Python and pandas
- Instant grading and a worked solution for every free question
- 11 Data Labs projects with their datasets
- Discussions, and posting your project repos for others to see
Premium
$12/ month
$36 billed every 3 months
Save 20% · Best for a job search
- Everything in Free
- 15 harder interview questions, labeled by company: Meta, Netflix, Airbnb and more
- Datasets for 3 advanced portfolio projects: fraud detection, RAG and data modeling
- AI grading for your projects when it launches, at no extra cost
- Every new Premium question and lab as it is added
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Why learners go Premium
The questions that decide the offer
Screening rounds test the basics. Final rounds push on window functions, running totals, reshaping and the edge cases that trip people up. Premium is where you practice those, each with instant grading and a worked solution.
Projects hiring managers remember
Anyone can clean a sales spreadsheet. A fraud model tuned for rare events, a RAG assistant that cites its sources, or a star schema with price history shows you can do the job. Premium unlocks the datasets for exactly these.
Priced for a job search
Most people prepare for a few months, not forever. The quarterly plan covers a typical search for $36, and the 14-day money-back guarantee means trying it is risk-free.
Everything you unlock today
Marked with a Premium badge across the site, and growing as new questions and labs are added.
15 interview questions
Minutes from order to doorstepInstacart · SQLhard
Win rate by sales repSalesforce · SQLmedium
Top restaurant in each cityDoorDash · SQLhard
Running account balanceStripe · Pandasmedium
Each user's top categoryPinterest · SQLhard
Longest trip without repeat citiesAirbnb · Pythonhard
Most-watched title in each countryNetflix · SQLhard
Posting on consecutive daysMeta · SQLhard
Month-over-month spend changeVisa · SQLhard
Missed minimum paymentsCapital One · SQLmedium
Card-testing patternsMastercard · SQLhard
Busiest hour per cityLyft · Pandashard
Holdings in long formatRobinhood · Pandashard
Search a rotated scheduleUber · Pythonhard
Stretches that hit a targetDoorDash · Pythonhard
Datasets for 3 Data Labs projects
Workday · AI ProjectHR Policy Assistant with RAGBuild a RAG assistant that answers employee questions from policy documents, cites its source and says so when the answer isn't there.
Airbnb · Data Engineering ProjectBookings Star Schema with Price HistoryModel bookings as a star schema that keeps listing price history, so past revenue stays correct when hosts change prices.
Razorpay · Data Science ProjectPayment Fraud DetectionBuild a classifier that flags fraudulent payments before they're approved, and pick a review threshold based on what fraud actually costs.
Every lab's brief stays free to read. Premium unlocks the dataset download.
Questions about Premium
- What stays free?
- Most of the library: 132 of 147 interview questions, each with instant grading, a worked solution and a discussion, and 11 of 14 Data Labs projects with their datasets. Every lab's brief is free to read, including Premium labs. AI grading of lab projects, once it launches, is part of Premium.
- How does billing work?
- Premium is $15 a month, $36 every 3 months or $120 a year in US dollars, billed in advance and renewed automatically until you cancel. In some countries, including India, you pay a local price in your own currency, shown on this page and at checkout. Any sales tax or VAT for your country is added at checkout.
- How do I cancel?
- Open the account menu and choose Manage subscription, then cancel. You keep Premium until the end of the period you have paid for, and you are not charged again.
- What if it isn't for me?
- Then you get your money back. Ask within 14 days of your first payment for a full refund, no reason needed.
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- Paddle, our online reseller and merchant of record. Paddle processes your payment, handles tax and sends your receipts. We never see your card details.
- Is this the career accelerator program?
- No. Premium is self-serve practice on this site. The accelerator program is separate, with its own application and fees.
See our Terms of Service, Refund Policy and Privacy Policy. Questions? Email amlanmohanty.info@gmail.com.
Your next interview won't ask the easy questions.
Practice the ones it will, and build the projects that get you there. Try Premium with a 14-day money-back guarantee.