How we keep 37,000+ free questions trustworthy
Brain Grain is used by students and aspirants who can't afford to revise from wrong answers. So trust isn't a slogan here — it's a process. This page shows exactly how the content is built, checked, and kept honest.
The work behind every question
✅ Checked against the actual book
Every answer is written against the real Samacheer Kalvi or NCERT chapter, or the official guide — not generated once and forgotten. Where a source scan is unclear, we mark it "please confirm" rather than guess, so you never revise from an invented answer.
🎯 Wrong options are real mistakes
A multiple-choice question is only as good as its wrong options. Every distractor has to be a mistake a real student would genuinely make — a common misconception or a specific slip — never filler. We deleted and rewrote 16 NEET chapters that failed this bar.
📊 Exam-accurate marking
Our mock papers are scored by a marking engine that is tested against the real NTA, TNPSC and board papers — negative marking, partial credit, multi-correct rules and all. Your mock score reflects what you'd actually get in the hall.
🔒 Automated quality gates
Before any change goes live it must clear automated checks — content validators, an SEO/indexing crawl, a text-accuracy gate, and a layout audit that renders pages at real phone widths. A broken or thin page can't reach you.
📚 Depth, not a demo
Every subject is built to real depth — full chapters, exercise questions, MCQs, important questions and previous-year papers — not a thin sample designed to push you toward a paywall.
🇮🇳 Bilingual, carefully aligned
Tamil questions are checked so the options line up with the correct answer — a class of bug we specifically test for — because a mistranslated option is worse than no translation.
What's covered
| Area | What you get | Questions |
|---|---|---|
| Samacheer Kalvi (Class 6–12) | Every subject, chapter-wise Q&A, MCQs, papers | 22,600+ |
| NCERT / CBSE (Class 6–12) | Intext + exercise solutions, chapter-wise | 5,400+ |
| TNPSC (Group 1 / 2 / 4) | Practice + mocks, with 1,900+ in Tamil | 3,600+ |
| NEET & JEE | All 106 chapters, full papers, all-India rank | 3,180 |
| CTET / TNTET | Bilingual practice with previous-year questions | 680+ |
Counts grow every week. Figures shown are rounded down from the live totals, so they stay accurate as more content ships.
Built to actually help you learn
🚫 Ad-free & distraction-free
No ads, no pop-ups, no clickbait. Nothing on the page is designed to pull your attention away from the chapter.
⚡ Fast on any phone
Mobile-first and lightweight, so it loads quickly on a modest phone and a 4G connection — the devices most students actually use.
🔥 Engaging & motivating
XP, streaks, a weekly leaderboard and a personal readiness path turn revision into a daily habit you want to keep.
❤️ Free because it should be
Most of Brain Grain is free — because cost should never be the reason a child or an aspirant can't prepare well. Optional paid packs help keep it running.
The learners behind the numbers
These are real usage figures — website analytics (Google Analytics) for reach and time, and on-site XP earned across every learner and guest. Updated daily and rounded down, so they only ever understate.
Engagement rate is the share of visits where a learner actually settled in to study (not a quick bounce). XP is awarded for practising questions, keeping streaks and completing daily tests.
Used Brain Grain? Tell us honestly.
Real reviews from real learners are the only testimonials we'll ever show. Yours helps the next student decide to trust us.