Pricing
Self-paced prep starts free. Upgrade when you want the medium and hard pads that look like the onsite.
Self-paced prep: easy coding pads, the interview question bank, and all guides.
$0/mo
Forever free
Most people start here
Unlock medium and hard pads across all data roles — the ones asked in real interviews.
$12/mo
Billed monthly
Original bank, not paywalled
3 free · 57 in Pro
One problem list, filter by role
One membership. The same pads and articles — not a separate video library glued on later.
310+ questions
SQL, modeling, orchestration, warehouses, ML, and behavioral — original prompts, not a leaked exam dump. Drill mode is one question at a time.
60 coding problems
3 easy pads stay free. 28 medium and 29 hard unlock with Pro. Tests run in this tab — no notebook, no warehouse account.
Mean
Easy · free
def arithmetic_mean(xs):
# Write in NumPy, Python, or PyTorch
return sum(xs) / len(xs)✓ Tests run in this tab
9 roles
A graph per role, ordered problem tracks, and original certification drills. Progress stays on this device.
| Surface | Free | Pro |
|---|---|---|
| Easy coding problems | Editor, tests, solutions | Editor, tests, solutions |
| Medium and hard coding problems | Locked | Editor, tests, hints, solutions |
| Interview questions | Full bank | Full bank |
| Blog, roadmaps, certs | Yes | Yes |
Can’t find what you need? Email srinivasa8511@gmail.com
The blog, role roadmaps, interview question bank, certification practice, cheat sheets, the SQL sandbox, and every easy coding problem. You can learn the grain of the warehouse without a card.
Medium and hard coding problems (57 pads today): the editor, tests, hints, and reference solutions. Easy problems stay free. Interview questions are not paywalled.
We process payments securely via Dodo Payments (global Merchant of Record). Dodo Payments handles tax/VAT compliance and supports Credit/Debit Cards, UPI, Apple Pay, Google Pay, and international local payment options in 150+ countries. After checkout you return to your settings page, and Pro activates on this device as soon as Dodo Payments confirms the payment.
Yes. You can manage or cancel your subscription anytime directly from your Dodo Payments customer portal or by emailing us. Your Pro access stays active through the end of the billing period you paid for, with no lock-in or cancellation fees. First payments can be refunded in full within 7 days; see the refund policy.
Analyst, BI, analytics engineer, data engineer, data scientist, ML engineer, MLOps, AI engineer, and architect. Filter the problem list by role — one list, every role.
Monthly is the most flexible. Annual is charged upfront at $99 (about $8.25/mo) and saves two months versus paying $12 each month. Features are the same.
A browser editor for SQL (SQLite in this tab) and Python (NumPy, plain Python, or PyTorch via Pyodide). Write code, run tests, and study the reference solution once the pad is unlocked.
Start with easy pads for free. Upgrade when you want the medium and hard set that matches a real screen.