How to make flashcards that actually help you remember
By the Braintoll team · · 7 min read
The short answer
To make good flashcards, understand the topic first, then write one specific question per card in your own words, with an answer you can recall in a few seconds. Split long lists into separate cards, and ask why and how as well as what. Answer before you flip, keep your cards in one large stack, and don't retire a card after one correct answer. Review over several days. Research suggests that making your own cards tends to beat premade ones, unless you only copy and paste.
On this page
Most flashcards fail before you study them. A card with a whole paragraph on the back can’t really be tested: you read it, nod and flip to the next one. A card that asks one clear question makes you pull the answer out of memory, and that effort is what makes it stick.
This guide shows how to write cards that do that, with before-and-after examples from several subjects, and how to study with them once they’re made. The rules draw on Piotr Woźniak’s well-known “20 rules of formulating knowledge” and on experiments with students using flashcards.
8 rules for good flashcards
1. Understand it before you write the card
Flashcards help you keep what you’ve understood. They’re a poor way to understand it in the first place. Woźniak puts this at the top of his list: don’t learn what you don’t understand. Read the chapter or watch the lecture first, then make the cards.
2. One fact per card
If a card asks for several things, you’ll remember some of them and still mark it as known.
| Front | Back | |
|---|---|---|
| Before | What do you know about mitochondria? | A paragraph on structure, function and DNA |
| After | What do mitochondria mainly produce? | ATP |
3. Ask a specific question
A bare topic on the front doesn’t tell you what to retrieve. A good question has one right answer.
| Front | Back | |
|---|---|---|
| Before | French Revolution | Long summary of causes and events |
| After | On what date was the Bastille stormed? | 14 July 1789 |
4. Use your own words
In experiments led by Steven Pan, published in 2023, students who paraphrased the material on their cards did best, and those who copied and pasted got no significant advantage from making their own. Rewording forces you to think about what a sentence means.
| Front | Back | |
|---|---|---|
| Before | Define opportunity cost. | Textbook sentence, copied word for word |
| After | What’s the opportunity cost of choosing A over B? | What you give up by not choosing B |
5. Split long lists
Lists are hard to memorize as one item, and Woźniak advises avoiding them. Break them into cards that each ask for one part.
| Front | Back | |
|---|---|---|
| Before | Name all 12 cranial nerves. | The full list |
| After | Which cranial nerve moves the muscles of the face? | VII, the facial nerve |
If you must know a list in order, add a mnemonic or practise it as a sequence, but don’t let it be your only card on the topic.
6. Ask why and how, as well as what
Students tend to write cards about details unless they’re told otherwise. In a 2018 study by Chunliang Lin and colleagues, more concept-level cards went along with better test results. If your exam asks for explanations, your cards should too.
| Front | Back | |
|---|---|---|
| Before | Inflation | Rising prices |
| After | Why do higher interest rates tend to slow inflation? | Borrowing costs more, so people and companies spend less |
7. Keep look-alikes apart
Similar items get mixed up in memory. Woźniak calls this interference and considers it probably the biggest cause of forgetting. When two cards keep colliding, add something that tells them apart.
| Front | Back | |
|---|---|---|
| Before | affect | to influence |
| After | The weather can ___ your mood. (affect or effect?) | affect: the verb |
8. Give vocabulary some context
A single word often has several meanings. A short sentence shows which one you’re learning, and how it’s used.
| Front | Back | |
|---|---|---|
| Before | tiempo | time |
| After | ¿Qué ___ hace hoy? (what’s the weather like?) | tiempo |
More on learning words in our guide to memorizing vocabulary.
Should you make your own flashcards?
Usually, if you have the time. In Pan’s experiments with college students, those who made their own cards beat those using premade ones in five out of six experiments, typically by about 10 percent on a test. The research isn’t unanimous: Lin’s study above found no general benefit from making cards, though those students also took longer to study.
Premade sets have another risk: they can contain mistakes, and you won’t notice when you don’t yet know the subject. If you use one, check it against your notes, and rewrite the cards that don’t make sense to you.
What about AI? The studies above didn’t test AI-made cards, so nobody can say exactly how they compare. Our own app creates cards with AI, so take this as coming from a maker of such a tool: it saves hours of typing, and it’s useful when the alternative is no cards at all. But read every draft, delete what you don’t need, and put the important ones in your own words. Our guide to turning a PDF into flashcards shows how.
How to study with flashcards
Good cards only work if you use them well. Four habits matter most:
- Answer before you flip. Say or write the answer first. Flipping straight away is rereading. Our guide to active recall explains why the effort counts.
- Use one large stack. Nate Kornell tested this in 2009: spreading study across one big stack worked better than studying several small stacks one at a time for 90 percent of participants. After the first session, though, 72 percent believed the opposite. Small stacks feel better because you get through them faster.
- Don’t retire a card after one right answer. In experiments by Kornell and Robert Bjork, students allowed to drop the cards they thought they knew learned slightly less than those who kept going through all of them. One correct answer today doesn’t mean you’ll know it next month.
- Come back over several days. Each review after a gap does more than another round today. With spaced repetition, an app works out when each card is due. On paper, a Leitner box does the same: a card you get right moves to the next compartment, reviewed less often, and a card you get wrong goes back to the first.
Which study methods work best around your flashcards is covered in how to study for exams.
Paper or app?
Pan’s studies didn’t compare paper with digital cards. What seems to matter is that you think about what goes on the card, and both formats allow that.
| Paper | App | |
|---|---|---|
| Good for | Drawings, formulas, no distractions | Schedule, large decks, always with you |
| Review schedule | By hand, with a Leitner box | Automatic |
| Weak point | Takes time and space | Your phone is right there |
For paper, we have free printable flashcard templates for Word and PDF. For apps, see Anki vs Quizlet.
Short cards fit into short moments
Cards written by these rules take a few seconds each, which makes them easy to use in small gaps. Braintoll builds on that: it shows a few of your cards when you open an app you’ve chosen to block, such as Instagram or TikTok. Answer them, mark enough as Easy, and the app opens for as long as you’ve set. Each card comes back on a spaced repetition schedule, so you don’t have to plan reviews or sit down for a session.
You can write your cards in the app, start from a preset, import an Anki deck with its progress, or have the AI draft them from a topic, notes or a PDF. Braintoll shows text only, so drawings and cloze cards are better kept in Anki or on paper. It’s free for one app with unlimited cards, on Android and iPhone.
Common questions
What should be on a flashcard?
One specific question on the front and a short answer on the back, in your own words. The answer should be something you can recall in a few seconds. If it takes a paragraph, split it into several cards. For vocabulary, add a short example sentence.
Is it better to make your own flashcards?
Usually yes. In a set of six experiments, students who made their own cards did better than those using premade sets in five of them, typically by about 10 percent. Copying and pasting removed the advantage, and rewording in your own words worked best. Not every study has found this benefit.
How many flashcards should I make?
As many as you have separate facts worth remembering, and no more. Don’t make a card for everything in the chapter: start with what’s likely to be in the exam and what you keep forgetting. There’s no proven best number, but ten good cards beat fifty you’ll never finish.
Are paper or digital flashcards better?
Neither has been shown to be clearly better. Paper is good for drawings and formulas and keeps your phone out of reach. Apps schedule your reviews automatically and handle large decks. Choose the one you’ll keep using.
How do you study with flashcards effectively?
Answer each card before you flip it, keep all cards in one large stack, keep reviewing cards after you first get them right, and spread your reviews over several days. Rate yourself honestly: a card you almost knew isn’t a card you knew.
Braintoll is not affiliated with Anki or Quizlet. All product names are the property of their respective owners.