Free AI tool
PDF to quiz — a practice test you can actually fail.
Most AI quizzes are easy for one reason: three of the four options are obviously wrong. Laxu AI pulls every wrong answer out of your own PDF, so elimination stops working and the score means something.
Why most AI quizzes are too easy
A multiple choice question is only as hard as its worst option.
Generic AI quiz
Which enzyme catalyses the rate-limiting step of the citric acid cycle?
- A. Isocitrate dehydrogenase
- B. Photosystem II
- C. Pepsin
- D. DNA polymerase
Three options are from other subjects entirely. You can answer this without having read the chapter.
Laxu AI
Which enzyme catalyses the rate-limiting step of the citric acid cycle?
- A. Citrate synthase
- B. Isocitrate dehydrogenase
- C. α-ketoglutarate dehydrogenase
- D. Succinate dehydrogenase
All four are enzymes of the same cycle, taken from the same chapter. Now you have to know which one.
The rule the generator works to is explicit: every wrong option must be a real term, value or claim that appears elsewhere in your source — typically the correct answer to a different question, or the thing students most often confuse this one with. If the document offers nothing that can plausibly compete with the answer, it writes a different question instead of padding the options out.
What comes back from one upload
The length of the test scales with the source, not with a slider you have to guess at.
| Source length | Multiple choice | True / false | Total |
|---|---|---|---|
| A handout or a few slides | 18 | 2 | 20 |
| A typical chapter | 22 | 3 | 25 |
| A long chapter or a full deck | 30 | 5 | 35 |
Questions that stand alone
You will never see according to the text or as the author states. Questions are written as if testing the subject itself, so they still work months later without the PDF open.
An explanation on every answer
Each question carries a short justification drawn from the source, so a wrong answer teaches you the material instead of just costing you a mark.
No fact tested twice
The generator is told to cover the source broadly and never test the same fact across both question types, so 25 questions means 25 different things.
How to make a practice test from a PDF
The order matters more than most people expect.
- 1
Upload the chapter you are being examined on
A PDF, lecture slides or scanned notes, up to 100 MB. The whole file is read before a single question is written.
- 2
Sit the test cold, before revising
Taking it before you feel ready is the point. A question you get wrong now is worth more than a page you reread and already knew.
- 3
Read the explanations, then retake
Every answer comes with a short explanation from the source. Retake the same quiz a day later and the gaps close.
Sitting a test you are not ready for beats rereading the chapter you think you know.
Roediger and Karpicke gave students a passage and then either another study period or a test. A week later the tested group recalled 61% and the rereading group 40% — even though the rereaders felt more confident at the time. The discomfort of being tested early is the mechanism, not a side effect.
Roediger & Karpicke, Psychological Science, 2006.
Made for the week before the exam
Medical and nursing students
Pharmacology and physiology chapters where the wrong answer is always another real drug or another real pathway. Generic quizzes are useless here; plausible distractors are the whole test.
Anyone sitting a multiple choice exam
MCAT, USMLE, bar prep, professional certifications. If the real paper uses four plausible options, practising against three silly ones teaches you nothing about the real paper.
Students revising from slides
A lecture deck becomes 25 questions covering the whole deck rather than the three slides you happened to reread. Coverage is the point of a generated test.
The quiz is one of four things you get
The same upload also produces flashcards on a spaced repetition schedule, structured notes, and a two-host study podcast. A practice test tells you what you do not know; the other three are how you fix it. There is no extra charge and no second upload.
PDF to quiz — common questions
How do I turn a PDF into a quiz?
Upload the PDF and Laxu AI reads it end to end, then writes a practice test from it. A short document gives you 20 questions, a medium one 25, and a long chapter 35. You can take it straight away, retake it as often as you like, and every answer comes with an explanation.
What kinds of questions does it write?
Multiple choice and true or false. The split leans heavily on multiple choice, because four plausible options test recall far better than a coin flip: a short source produces 18 multiple choice and 2 true/false, a long one 30 and 5.
Where do the wrong answers come from?
From your document. Every distractor is a real term, value or claim that appears somewhere else in the same PDF, usually the correct answer to a different question or the thing students most often confuse this one with. Nothing off-topic is invented to pad the options out.
Are the questions just reading comprehension?
No. Questions are written to stand on their own, so you will never see phrasing like according to the text or as the author states. They read like exam questions about the subject, which means you can answer them months later without the PDF in front of you.
Can I see why an answer was wrong?
Yes. Every question carries a short explanation grounded in the source, so a wrong answer tells you what the material actually says rather than just marking you down.
Can I retake the quiz?
As many times as you want, and retaking is the point. The research on the testing effect is about repeated retrieval, not a single score, so the second and third attempts are where most of the learning happens.
Does it work with scanned PDFs and lecture slides?
Yes. Slide decks and scanned chapters both work, because the text is read off the page. Files up to 100 MB on the web, 50 MB in the iOS app and 40 MB on Android.
Is it free?
Your first upload is free with every feature switched on, and no card is required. That one upload gives you the quiz plus flashcards, notes and a study podcast. Pro is $4.99 a month or $39.99 a year for unlimited uploads.
Find out what you don't know — free.
One PDF, 20 to 35 questions, no card required.
A quiz can come from more than a PDF