Best DataLemur Alternatives in 2026: Free and Paid Options Compared

The best DataLemur alternatives are PracHub for a free start on recent, company-tagged SQL, analytics and statistics questions, StrataScratch if you want to run and grade code against real datasets, and Interview Query if your loop leans on product sense and A/B testing. DataLemur itself is cheap ($15 a month or $60 a year as of October 2026), so the reason to leave is coverage, not price: its logged-out catalog listed 106 questions when checked on October 14, 2026, and only four companies had five or more.

Pricing and product details were checked on October 14, 2026.

Quick Verdict

Choose PracHub when DataLemur's free set has run out and you need more real questions from the company you are interviewing with, across SQL, experimentation and statistics, without paying first. PracHub is free to start with an optional paid tier.

Choose StrataScratch when you want a paid product that executes your SQL or Python against real datasets and diffs the result, and you can accept $139 a year (as of October 2026) for it. Keep DataLemur instead if your next round is a single analytics SQL screen at Amazon, Meta or Google and $60 a year for hints and full solutions on a short list is all you need.

Why Candidates Look for DataLemur Alternatives

The catalog is small and company depth is thin. When checked on October 14, 2026, the logged-out questions page listed 106 questions (54 SQL, 39 Python, 7 statistics, 5 machine learning, 1 probability) across 46 company labels. Only Amazon (11), Facebook (9), Google (7) and Microsoft (5) reached five; 22 companies had a single question.

The counts do not agree. The pricing page promises 100+ SQL and 70+ data science questions and the one-time bundle says 250+, yet only 13 statistics, ML and probability questions are visible logged out.

You cannot see what you are buying. The public catalog does not mark which questions or full solutions are free, and its terms say it does not offer "any discounts or free trials", only free accounts or paid subscriptions.

The money terms are strict. Fees are non-refundable except where the law requires; refunds are considered case by case by emailing the founder, and cancelling only stops the next renewal. Prices are "subject to change without notice", and its own blog still quotes Premium at $10 a month against $15 on the pricing page.

Pipeline and data-processing practice is thin, by a competitor's account. On October 14, 2026 the questions page filtered by five categories only: SQL, Python, Statistics, Machine Learning and Probability. DataDriven, a competitor rather than a candidate, says DataLemur has no pipeline design or Spark practice and that its Python set is generic algorithm drills such as Two Sum. On the 2022 Show HN thread, the founder said difficulty labels are set "just off the vibes".

For what the catalog does well, read our honest DataLemur review.

What to Look For in an Alternative

1. Real, dated questions over generic drills. A recent loop shows the bar; a textbook exercise shows the syntax.
2. Depth at your target company. Count the questions for the one company you are interviewing with, not the logo wall.
3. Written solutions that explain the reasoning. Interviewers ask follow-ups, and a bare final query does not prepare you for them.
4. Free access you can check before paying.
5. Coverage past SQL. Data scientist loops add experimentation, causal inference and statistics rounds.
6. Refund terms you have read. All three paid products below call fees non-refundable in their terms. StrataScratch's pricing page adds a 5-day money-back guarantee; for the other two, the free layer is your trial.

The Shortlist

We compare the three paid data platforms head to head in DataLemur vs StrataScratch vs Interview Query. If LeetCode's SQL problems are your other candidate, see LeetCode SQL vs DataLemur.

PracHub

PracHub is a bank of real interview questions from recent loops, with in-depth written solutions, and most questions are free. As of October 14, 2026 it holds more than 12,000 questions from more than 550 companies; more than 8,000 are free and more than 7,500 have a written solution.

The data categories are where it outgrows DataLemur: more than 700 SQL and pandas questions, more than 950 analytics and experimentation questions, more than 600 statistics and math questions and more than 800 machine learning questions. On the four companies DataLemur tags most, PracHub lists more than 850 Amazon questions, more than 1,200 Meta questions, more than 600 Google questions and more than 250 Microsoft questions (all as of October 14, 2026).

Asked at Amazon: Find recommended friend pairs by shared songs A data scientist SQL question: from listens and friendships tables, return the user pairs that qualify as recommended friends on a given date because of songs they share.

Asked at Google: How would you use propensity score matching here Engaged users opt in to a non-randomized feature, and you must estimate its effect on 7-day retention from observational data. DataLemur's category filter has no experimentation or causal-inference option.

The trade-off: PracHub is built around written solutions you argue with, not a code grader. The full head to head is in DataLemur vs PracHub.

StrataScratch

StrataScratch is the closest product to DataLemur, and bigger. As of October 14, 2026 its homepage claims "1000+ real coding and concept questions" across SQL, Python, ML system design and statistics. Its connector documentation lists a code runner for SQL, Python, PySpark, R and several SQL dialects with a row-level diff on each check, and Data Labs adds take-home projects in hosted notebooks. It costs $24 a month, $139 a year or $289 one-time, and the free plan includes 75+ coding questions with solutions, hints and walkthroughs.

The drawback: author solutions beyond that free set are Premium-only, and the paperwork disagrees with itself. The pricing page advertises a 5-day money-back guarantee while the terms call fees non-refundable.

Interview Query

Interview Query sells breadth. Archived 2026 snapshots of its site list questions, learning paths, company guides (its /companies page showed 9,221 companies in March 2026), 50+ take-home challenges, peer mock interviews, coaching and an AI interviewer. Its January 2026 pricing page lists product intuition, SQL, statistics and A/B testing, machine learning and probability among its question areas, which suits loops heavy on product cases. Its own April 2026 comparison post lists $69 a month, $169 a year and $299 one-time; the live pricing page was bot-blocked when checked on October 14, 2026.

The drawback is cost against what you can verify. Question cards in a March 2026 snapshot were marked "Locked", its own pages give 500+, 1,000+ and 35,000+ as the bank size, and its May 2026 terms make every fee non-refundable once you have accessed content.

Free Alternatives to DataLemur

• PracHub: most questions are free (more than 8,000 as of October 14, 2026), including SQL, experimentation and statistics questions tagged to the company that asked them.
• StrataScratch's free plan: 75+ coding questions with solutions, hints and walkthroughs, the SQL and Python learning paths, and 50 AI credits a month (as of October 14, 2026).
• DataLemur's own free layer: a free account, a free SQL tutorial for data analytics and a free 9-day data interview crash course.
• Interview Query: a free data science challenge quiz and a newsletter of practice questions. Beyond that, the archived bank appears gated.

For running code at zero cost, StrataScratch's free plan is the strongest; for real, company-tagged questions, start with PracHub.

When DataLemur Is Still the Better Choice

• Your next round is an analytics SQL screen. A short, curated list with hints and full solutions is efficient. When checked on October 14, 2026, its topic tags showed 38 window-function questions and 40 CTE or subquery questions.
• You are on a tight budget. $60 a year (as of October 2026) is the lowest price among the three paid products here, and the free tutorial and crash course cost nothing.
• You own "Ace the Data Science Interview". When checked on October 14, 2026, 28 questions were tagged to Nick Singh's book, so you can practice its problems interactively.
• You are targeting Amazon, Meta or Google SQL screens. Those are its deepest company tags, backed by company-specific blog guides.
• You want the founder's time. The $300 one-time bundle includes a 1-hour call with Nick Singh, a signed copy of his book and lifetime access.

How to Switch

1. Diagnose with free questions first. Do five free questions from your target company on PracHub before you pay anyone.
2. Pick the company hub. Open your target's hub, such as Amazon for the screens DataLemur tags most, and sort by round: a SQL screen needs SQL reps, a data scientist onsite adds experimentation and statistics.
3. Time-box the subscription. If you buy DataLemur, StrataScratch or Interview Query, buy one period for a dated interview window and cancel early; all three sets of terms call fees non-refundable.
4. Spend on recency last. Once the basics are solid, the highest-value hour is a question the same company asked recently, with a written solution you can argue with.

Practice these on PracHub

Real questions from recent data loops, grouped by round. All four are free to read.

SQL and pandas (SQL: zero-filled DAU, rolling 30-day MAU and a user-ID rehash, asked at Glean); more in the SQL and pandas questions.

Analytics and experimentation (Conservative wait estimates cut conversion and pickup time, asked at Waymo · Measure game monetization and validate a reporting repair, asked at Meta); more in the analytics and experimentation questions.

Statistics and math (Choose classification metrics under asymmetric costs, asked at Microsoft); more in the statistics and math questions.

Preparing for a full loop rather than one round? Browse every data scientist interview question, or go straight to the SQL interview questions page.

Frequently Asked Questions

What is the best free alternative to DataLemur?

PracHub, if you want real interview questions tagged to the company that asked them. As of October 14, 2026, more than 8,000 of its questions are free, across SQL, analytics, experimentation and statistics. If you mainly want to write and run code for free, StrataScratch's free plan includes 75+ coding questions with solutions and its SQL and Python learning paths.

Is there a cheaper alternative to DataLemur?

Not among the three paid platforms compared here. As of October 2026 DataLemur costs $15 a month or $60 a year, against $24 a month or $139 a year for StrataScratch and $69 a month or $169 a year for Interview Query (from its own April 2026 post). The cheaper route is free practice: PracHub is free to start with an optional paid tier, and most of its questions are free.

Is DataLemur worth paying for compared with free options?

Only if its short list matches your next round. Its logged-out catalog listed 106 questions when checked on October 14, 2026, and only Amazon, Facebook, Google and Microsoft had five or more. It offers no free trial and its fees are non-refundable except where the law requires, so work through the free questions here and on its free account first.

Is StrataScratch better than DataLemur?

StrataScratch is bigger and runs your code against datasets in several languages, with take-home labs and AI mock interviews, but it costs more ($139 a year versus $60 as of October 2026), and author solutions beyond its free 75+ coding questions are Premium-only. DataLemur is the better buy for a focused SQL screen on a budget; StrataScratch is the better buy for broad, executable data science practice.

Can I use DataLemur and PracHub together?

Yes. Use DataLemur's curated list to drill SQL patterns such as window functions and CTEs, and use PracHub for recent questions from your target company and for the rounds DataLemur lists little or nothing for: statistics (7 questions visible logged out on October 14, 2026) and experimentation cases, which its category filter does not include.

Final Verdict

DataLemur is a fair deal for what it is: a cheap, curated SQL list with hints and full solutions, built by the author of Ace the Data Science Interview. The case against it is depth, not price: 106 questions visible logged out, sold with no free trial and fees that are non-refundable except where the law requires.

For most candidates the better order is free first. Use PracHub for real, company-tagged questions across SQL, experimentation and statistics, add StrataScratch if you need a code runner, and keep DataLemur for a final pass on SQL screens if its list fits your target. Start with PracHub's SQL interview questions.