HSC and Years 7 to 10, built on the NESA syllabuses and marked like the real exam

HSC study that
actually sticks.

Practise real HSC exam questions, get marked in seconds, and remember it on test day.

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Built on the official NESA syllabuses · made in Sydney by people who just sat the HSC

Modern HistoryBiologyChemistryPhysicsEnglish AdvancedMathematicsEconomicsLegal StudiesBusiness StudiesEngineeringGeographySociety & CultureVisual ArtsSoftware EngineeringAncient HistoryDesign & TechnologyDramaMusicModern HistoryBiologyChemistryPhysicsEnglish AdvancedMathematicsEconomicsLegal StudiesBusiness StudiesEngineeringGeographySociety & CultureVisual ArtsSoftware EngineeringAncient HistoryDesign & TechnologyDramaMusic

Free, no account needed

Get a paper markedThree real exam questions for your subject, marked in seconds with what to fix. ATAR calculatorYour HSC marks in: scaled marks, your aggregate, an estimated ATAR and what you need. Grade calculator, Years 7 to 10Your task marks in: your A to E grade so far and what you need on the rest. NAPLAN practiceReading, conventions, numeracy and writing for Years 7 and 9, with results in NAPLAN's levels.
45
HSC subjects covered
Built directly from official NESA-published syllabus documents, the same ones used by NSW teachers and schools.

Everything you get, in five places

Pick a door to see what it actually produces and what else is inside. One plan covers all of it.

Three steps, then you’re studying.

No setup weekend, no course to work through first.

1

Tell us your subjects

Sign up free and pick the HSC courses you’re actually sitting. Every tool then stays inside them, with no wading through subjects you don’t take.

2

Pick a tool and go

Sit a practice paper, get an essay marked, decode a dot point, or just ask the tutor. Answers come back marked with the reason for each mark, not a score on its own.

3

It keeps itself organised

Everything you generate is saved and filed by subject automatically, and your weak topics build up as you go, so the next session knows where to start.

Start free No card. Free tier stays free.

Why Study Decoder over a generic AI?

Other tools do one of these things. We built every one of them around the NSW HSC syllabus, so you stop juggling four apps and a chatbot.

← swipe to compare →
Feature HSC-specific AI Generic chatbot Video lessons Notes & tutors
Built on the official NESA syllabusEvery dot point, every module, every band descriptor. ✓ ✗Generic, not NSW ✓ ✓
24/7 AI tutor that actually teachesSocratic coaching, LaTeX maths, voice input. ✓ ✓No HSC context ✗Pre-recorded videos ✗Notes and forums
Full 3-hour timed exam simulatorMC + short answer + extended response, auto-marked. ✓ ✗ ~Topic quizzes only ~Past papers PDF
AI marks your work to band levelPaste your answer, get a mark + specific feedback. ✓ ~Generic feedback ✗ ✗
Conversational flashcards + spaced repetitionAdaptive SR engine that schedules every review. ✓ ✗ ✗ ✗
Personal mastery mapA 3D map of every dot point you've practised, updated as you revise. ✓ ✗ ~Progress bars only ✗
For tutoring centresSet papers, marked automatically, weak topics across your students. ✓ ✗ ✓Separate school plan ✗
Built & supported by HSC graduates in SydneyAussie-built, not a Silicon Valley import. ✓ ✗ ✓ ✓
Entry priceWhat you'd pay to actually use it daily. Freeor $19.99 lifetime (one-time, until 5 Nov) $20/moUSD · generic GPT, no HSC $15-25/moAUD · per subject tiers Free notesPaid lectures extra
Pricing as of 2025. Comparison based on each provider's public pricing & features. See our pricing ↓

Simple, honest pricing

Start free, no card required. Upgrade when you're ready.

Lifetime deal · ends soon

Pay $9.99 once and use everything, forever.

A one-time payment for lifetime access. You will never be charged a monthly bill.

What you get Free Starter Lifetime (founding) Plus most popular Pro
Daily AI uses 8 / day 50 / day Unlimited 200 / day Unlimited
Full HSC papers 1 a week Unlimited Unlimited Unlimited Unlimited
Tutor 15 messages a chat Unlimited Unlimited Unlimited Unlimited
Marking Answers up to 6 marks Everything Everything Everything Everything
Essay and assignment marking ✗ ✓ ✓ ✓ ✓
Whole papers marked, typed or on paper ✗ ✓ ✓ ✓ ✓
Prepared essay (coached to full marks) ✗ ✓ ✓ ✓ ✓
Papers on topics you choose, or your weak ones ✗ ✓ ✓ ✓ ✓
Mistakes deck ✗ ✓ ✓ ✓ ✓
Print papers ✗ ✓ ✓ ✓ ✓
AI quality Basic Advanced Advanced Advanced Flagship
Response depth Short Full step-by-step Full step-by-step Full step-by-step Exam-grade
Essay marker depth Basic Standard Standard Standard Flagship, full Band 6 rubric
Band 6 model answers ✗ ✓ ✓ ✓ ✓
Predicted ATAR estimate ✗ ✓ ✓ ✓ ✓
Per-tool daily caps Strict Eased Removed Removed Removed
Priority response speed ✗ ✗ ✗ ✗ ✓
Early access to new tools ✗ ✗ ✓ ✗ ✓
Billing Free forever $4.99 / mo $9.99 once $7.99 / mo $9.99 / mo

Free includes 3 days of everything when you sign up. Unlimited means unlimited for normal study use.

Free
$0
Always free · no card
  • ✓Every tool, in all five doors
  • ✓8 AI uses/day + 3 free days unlimited on signup
  • ✓Streaks, games, leaderboard
  • ✗Basic AI · shorter answers
Start free

Monthly subscriptions open once the founding lifetime offer closes. Grab the lifetime deal above for the cheapest path in.

Your essays, chats and uploads stay tied to your account, never sold, never used to train external AI.

Frequently asked

What people ask before they start. Tap a question to open it.

Why do I study but forget everything in the exam?
Because re-reading notes feels like learning but barely sticks. Your brain keeps what it has to actively pull back out, so you remember more by testing yourself than by reviewing. Study Decoder is built around that: here's the full breakdown of why you forget, or jump straight into conversational flashcards and practice questions that make it stick.
How do I actually remember what I study for the HSC?
Three things, on repeat: active recall (test yourself instead of re-reading), spaced repetition (review just before you'd forget), and real exam-style questions under pressure. Full routine here, or let our spaced-repetition flashcards and free HSC practice questions handle the schedule for you.
How is this different to ChatGPT?
ChatGPT isn't trained on the syllabus. Our tools are built directly on the official NESA documents, and they're fully interactive, so you can chat, follow up, and dig deeper into any topic.
Which subjects do you support?
All 45 NSW HSC (Stage 6) subjects across English, Maths, Sciences, HSIE, Creative Arts, TAS, PDHPE and VET, plus Years 7 to 10 Drama 7-10, English, Maths, Music 7–10, Photographic and Digital Media 7–10, Physical Activity and Sports Studies, Science, Technology 7–8, Visual Arts 7–10 and Visual Design 7–10 for junior students.
Is there a free version?
Yes. You can try every tool for free with daily limits. Upgrade only if you want unlimited use, longer chats and full access to PDF exports.
Will the answers actually match what NESA wants?
Our bots reference the syllabus dot-points, glossary and marking guidance directly. Practice questions are styled like real HSC items, and feedback is mapped to the criteria markers actually use.
Can I cancel anytime?
Lifetime access is a one-off payment, so there is nothing to cancel and no recurring charge. Monthly plans, once they open after the lifetime offer closes, are month-to-month and cancel in one click from your account.
Is my data private?
Your chats and uploads are tied to your account and never sold. We only use them to power the tools you're using right now, and nothing else.
Still curious? Drop us a message

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