Start free. Upgrade for worked solutions across the full question bank.
Prices shown in your local currency. VAT/GST included.
A permanent free tier — not a trial
Cancel anytime — no lock-in
Everything in Free, included
TierOnePrep detects your region and charges €9.99/mo across Europe and $11.99/mo in the US and rest of world. In India, Pro is sold as prepaid access instead of a subscription — ₹499 for one month, ₹999 for three, or ₹1,699 for six, paid once with no auto-renewal. The price shown on this page is already the one you will be charged, VAT/GST included where applicable.
Yes. Outside India, Pro is a monthly subscription with no lock-in — cancel anytime from the billing portal and you keep Pro access until the end of the current billing period. In India there is nothing to cancel: access is prepaid for the term you chose, nothing is ever charged again, and no card mandate is set up.
Free gives you a set of fully unlocked practice questions - full worked solutions, walkthroughs and visualizations included, not previews - plus every quiz, the daily question, the interview concepts library, topic pages, the estimation tools and two complete behavioral guides, with no account required. Pro adds the rest of the bank: 140+ questions in total, 45+ interactive design walkthroughs across system design, cloud architecture and low-level design, 90+ coding problems with step-by-step algorithm visualizations and full worked solutions in multiple languages, and eight more behavioral guides.
TierOnePrep's free tier is a permanent trial rather than a time-limited one - questions across coding, system design and low-level design are always free and always fully unlocked, so you can judge the quality of the solutions themselves before paying.