How to make flashcards from a PDF: three methods compared

By oosync editorial team · Updated 2026-10-15 · 3 min read

A PDF is one of the most common things students are given to learn from: lecture handouts, chapters, articles, slide exports. Turning it into flashcards is a good idea, because flashcards make you practise recall, and spaced review keeps that practice going over weeks. The question is how to do it without spending more time making cards than studying them.

Here are three methods, from fully manual to mostly automatic, with honest trade-offs.

Before you start: what makes a good flashcard

Whichever method you use, the same rules apply:

• One idea per card. If the answer is a paragraph, split it into several cards.
• Ask questions you could be asked. "Why does X happen?" is better than "X:".
• Use cloze cards for terms in context. "The [...] is the powerhouse of the cell" works for vocabulary and key terms.
• Keep the answer short. You should be able to check it in a few seconds.
• Skip trivia. Page numbers, author names and dates rarely matter unless your exam asks for them.

For more on writing cards, read how to make good flashcards.

Method 1: by hand, on paper or in a notes app

How: Read one section of the PDF. Close it. Write questions on one side of a card and answers on the other, from memory where you can, then check against the text.

Time: roughly 30 to 60 minutes per chapter.

Pros: Deciding what to card and phrasing it in your own words is excellent learning in itself. Paper cards need no software.

Cons: Slow, and paper decks make spaced review harder to manage. You have to sort cards into "know" and "don't know" piles yourself.

Best for: small amounts of high-value material, such as the core theory of one module.

Method 2: in Anki (or another spaced-repetition app)

How: Read the PDF and type cards into Anki as you go: a question-and-answer card for explanations, a cloze card for terms. Copy short definitions directly, but rewrite explanations in your own words.

Time: similar to writing by hand, slightly faster if you type quickly.

Pros: Anki schedules reviews for you with spaced repetition, so each card comes back just before you would forget it. It is free on most platforms, and widely used in medicine and law.

Cons: You still write every card yourself. It is easy to over-produce cards and end up with hundreds of reviews a day.

Best for: subjects with a lot of material to memorise over a long time.

Method 3: generate cards from the PDF with AI, then edit

How: Upload the PDF to a tool that generates flashcards from its text. Review the draft deck: keep the good cards, rewrite the vague ones, delete the trivial ones.

Time: a few minutes to generate, plus 10 to 20 minutes to edit a chapter's worth.

Pros: Fast, and it covers the whole document. Useful when you are short of time or the reading list is long.

Cons: You skip the learning that comes from making cards yourself, and generated cards can be shallow, overly long or focused on the wrong details. Editing is not optional.

Best for: long readings, revision under time pressure, and getting a first deck you will then improve.

The method that works best for most students

Combine them: generate a draft deck from the PDF, then edit every card into your own words and add one or two cards of your own for each idea the generator missed. You get the speed of method 3 and much of the learning of method 1. Then review a little every day, rather than a lot the night before.

Making the review stick

• Review daily, briefly. Ten to twenty minutes a day beats two hours once a week.
• Say the answer before you flip. Peeking and thinking "I knew that" does not count.
• Suspend cards you have truly mastered and fix cards you keep getting wrong; a card you always fail is often a badly written card.
• Pair cards with practice questions. Flashcards build knowledge; a quiz or practice exam tests whether you can use it.

Doing it in oosync

In oosync you add a PDF (or PowerPoint, Word or EPUB file) to a module and generate flashcards from the whole material or one section. You get question-and-answer and cloze cards, with checks that drop trivial or yes/no cards, and an Anki-style scheduler that shows what is due today. You can edit or suspend any card, make your own from any highlight, and export the deck to Anki. See AI flashcards from your slides and notes for details.

As with any generator, treat the deck as a draft. If a card does not test something your lecturer would ask, edit it or delete it.