StrataScratch has the bigger bank (1000+ coding questions across SQL, Python and R), verified provenance, and — as of September 2026 — a $19/month Premium with AI mock interviews. SQL Quest has the bigger free tier (226 of 299 challenges, no signup), the wrong-answer diagnostic, and an adaptive Coach on the free plan. Side-by-side without the hype — including the cases where StrataScratch is genuinely the better pick.
226 FREE of 287
Every Easy + Medium, 6 Hard previews
AI Coach (Claude)
Plain-English Q&A
No signup needed
Browser-only, instant
Partly. StrataScratch has a real free plan, but most of the bank and every AI feature sit on Premium. Here is what each free tier gives you, as listed on 2026-09-07.
Verdict: StrataScratch's free plan is a usable first pass at 75+ questions, not a teaser — but there is no free Premium (students and educators get up to 20% off, and paid plans carry a 5-day money-back guarantee). If the goal is free SQL practice rather than StrataScratch specifically, SQL Quest's free tier is 226 challenges, Coach included, no account. Plan-by-plan pricing is below.
Pick SQL Quest if…
You want the bigger free tier without creating an account — 226 of 299 challenges against StrataScratch's 75+. You want a tutor that explains why your query is wrong, row by row, instead of an expected-output table. You're learning SQL, not just grinding interview questions, and want a Coach that adapts as you improve. You don't need Python or R — you only care about SQL.
Pick StrataScratch if…
You're prepping for a data-scientist or ML role that tests SQL plus Python or R — StrataScratch covers all three, with 50+ data projects and AI mock interviews on Premium ($19/mo as listed 2026-09-07). You've already exhausted SQL Quest's 299 challenges and want pure volume (1000+ coding questions). You value verified provenance ("this is the actual question Meta asked") more than diagnostic feedback.
Use both if…
SQL Quest as your daily driver (the free tier covers most SQL prep), StrataScratch Premium for the final stretch when you want maximum volume on real, company-labeled questions or a Python half. Most users don't need both — but if interview prep is your full-time focus for 6+ weeks, the combination beats either one alone.
13 features that matter when you're prepping. Re-verified September 2026 — StrataScratch column read from their pricing page on 2026-09-07.
Re-verified September 2026. StrataScratch features and pricing change — check their site for the latest.
Common gripes from candidates who hit the StrataScratch paywall or got tired of staring at "wrong" with no diagnosis.
StrataScratch's free plan is 75+ questions — a fair first pass, but the other 900+ and every AI feature are Premium. SQL Quest's free tier is the product — 226 of 299 challenges (every Easy and Medium plus 6 Hard previews), the AI Coach (daily quota), the 9-skill Skillmap, every sector track, all 30 company pages. Most candidates ship interviews on the free tier alone.
Your query produces wrong results. StrataScratch shows you the expected table — squint and find the diff yourself. SQL Quest tells you: "Row 3, column total_revenue, your value 4,820 — expected 4,920. You included refunded orders." Same wrong query, two completely different debugging experiences.
Stuck on a window function? Type the question in plain English. Claude reads your query, schema, and expected output and explains what's actually wrong — on the free tier, with a daily quota. StrataScratch's AI chat assistant is Premium-only and metered by credits; on the free plan you have the discussion boards.
StrataScratch is a question library — you decide what to do next. SQL Quest's Coach picks the next step: lesson when you're missing a concept, drill when a skill is rusty, mastery check when you're ready to test up. Less decision fatigue, more forward motion.
SQL Quest's 9-axis radar shows which skills are weak in numbers (Subqueries & CTEs at 32, Window Functions at 41, Joins at 78). The Coach then drills the weak axes specifically. StrataScratch tags topics on questions but doesn't aggregate them into a measurement you can act on.
▶ Try one free Medium: Department Performance Rate A percentage-per-group question, about a minute, no account and no card.
SQL Quest
Free → $29/mo or $99/yr
Free includes:
226 of 299 challenges — every Easy and Medium, plus 6 Hard previews
AI Coach (Claude) — daily quota
Adaptive Coach + 9-skill Skillmap
All 3 sector tracks (finance, real estate, manufacturing)
All 30 company interview pages
Wrong-answer diagnostic · no signup to start
Pro adds:
All 74 Hard challenges
AI Tutor without the free tier's daily cap
Full Mock Interview bank, all Daily difficulties, 30-Day Challenge
StrataScratch
Free (75+ questions) → $19/mo · $97.30/yr · $202.30 lifetime
Yearly and lifetime shown with a 30% promotion applied at checkout (list $139/yr, $289 lifetime). As listed 2026-09-07.
Free includes:
75+ coding questions with hints and solutions
50 AI credits per month
SQL & Python learning paths, concept questions
User solutions on the free questions
Premium adds:
1000+ coding questions (SQL, Python, R) + 500+ ML/stats/system-design
AI chat assistant for hints — 1,000 credits/mo (25,000 one-time on Lifetime)
AI mock interviews + AI grading
50+ data projects, cloud notebooks, community boards
5-day money-back guarantee; students & educators up to 20% off
StrataScratch prices as listed on platform.stratascratch.com/pricing on 2026-09-07. SQL Quest prices from the in-app Pro modal. Both change — confirm before you pay.
Not a hatchet job. Real cases where StrataScratch wins.
📚 Pick StrataScratch if:
You're prepping for a data-scientist or ML role that tests SQL plus Python or R, or hands you a take-home. StrataScratch covers all three languages and lists 50+ data projects with cloud notebooks; SQL Quest is SQL-only by design.
You want AI mock interviews. StrataScratch Premium includes an AI interviewer with grading; SQL Quest's Mock Interview mode is a timed question set, not an interviewer.
You've already exhausted SQL Quest's 299 challenges and want pure volume. StrataScratch lists 1000+ coding questions across its three languages.
Verified provenance matters to you — "this is the actual question Meta asked in 2024" with high confidence on the source. StrataScratch curates with strong sourcing claims.
You learn well from peer discussion threads. StrataScratch's community is active; SQL Quest leans on AI explanation instead.
Your interview is in 1-2 weeks and you want maximum cram-bank density. SQL Quest's adaptive Coach is built for the 4-12 week ramp; StrataScratch's flat list is faster to grind through.
If two of those bullets describe you, StrataScratch is probably the right call. If three of them don't, SQL Quest is faster and cheaper.
We used both platforms as a candidate would. On StrataScratch we created a free account in July 2026 and counted the questions reachable without paying; for this September update we re-read their public pricing page (platform.stratascratch.com/pricing) on 2026-09-07 and quote its numbers as listed — 75+ free questions, $19/mo, $97.30/yr and $202.30 lifetime, the latter two shown with a 30% promotion applied automatically at checkout (list $139 and $289). On SQL Quest we ran the no-signup flow and solved problems across Easy, Medium, and Hard to feel the wrong-answer diagnostic and the AI Coach first-hand; SQL Quest counts (299 challenges, 226 free, 30 company pages, 9 skills) are computed from the live content bank on 2026-09-06. The comparison table reflects what was live and listed, not marketing claims. Both platforms update their banks often — we re-verify on each edit. This page was last re-verified in September 2026. We also keep an honest "when StrataScratch is the better pick" section above, because a comparison that never concedes the other side wins isn't a comparison — it's an ad. If a number here looks off, the provider likely changed it since; always confirm on their site before you pay.
Open SQL Quest, start solving, see the AI Coach and the wrong-answer diagnostic in action. Every Easy and Medium challenge is free forever.
Try SQL Quest Free ⚡▶ Or start on one question: Department Performance Rate
or browse the free exercise set →
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