Spaced repetition software: What it is and how to use it to learn Chinese

Are you tired of learning Chinese characters and words only to forget them a day, a week or a month later?

What if there were a simple method that would allow you to remember almost everything you learn, and that didn’t take too much time and energy to use?

There is: spaced repetition!

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40 minutes per day to remember 30,000 Chinese characters and words

I used spaced repetition to learn and maintain almost 30,000 characters and words in Chinese, and it didn’t take more than 40 minutes per day to maintain this fairly extensive vocabulary.

Naturally, it took longer to learn all these characters and words in the first place, but spaced repetition is (or at least should be) about remembering what you have learnt, rather than learning entirely new things.

I wasn’t able to learn and remember almost 30,000 characters and words because my memory is great or because I have an innate talent for languages; anyone can achieve this with spaced repetition, even if few will take it as far as I did.

Spaced repetition works well whether you study 40 minutes or 40 hours per week

At the time, I was studying full-time, so 40 minutes per day was considerably less than 10% of my total study time. When I focused the most on vocabulary (including learning new characters and words), spaced repetition rarely exceeded 20% of my study time.

Spaced repetition is extremely efficient in the sense that you get a lot of bang for your buck, so it works really well even if you’re studying Chinese for only a few hours per week.

In this article, we’re going to explore spaced repetition for learning Chinese. We’ll start with the basics: what it is and how it works, then move on to what it can do for you as a learner of Chinese.

What is spaced repetition?

To summarise it in just one sentence, spaced repetition is a research-based way to spread reviews out over time to maximise the effectiveness of each review.

In psychology, this is called the spacing effect, and it essentially means that reviews spread out over time are many times better for later recall than reviews massed together.

Here are the two approaches applied to learning a new Chinese character. In each scenario, we assume that the character is reviewed ten times:

1. Spaced repetition: You learn about the character initially, then you check if you still remember it a few minutes later, then an hour later, then a day later, a few days later, a week later, and so on. If you forget it, you reset or drastically decrease the interval to the next review. With spaced repetition, each review will feel hard.
2. Massed repetition: You learn about the character initially (same as above), but then you review it over and over in the same session. As you review, you will feel like you know the character better and better, and towards the end of the session, recalling how to write the character will be trivial.

These two approaches take up the same amount of time, but the former is, as mentioned, many times better than the latter.

Spaced repetition always wins in the long run

If you have a test in an hour, massing your repetitions together works, but if you want to remember the character long term, spaced repetition is the only way to go.

I wrote more about cramming vs. spaced repetition here: Cramming vs. spaced repetition: When to use which method to learn Chinese.

Cramming vs. spaced repetition: When to use which method to learn Chinese

While spaced repetition is not strictly better in every situation, it always wins in the long term. And learning Chinese is a long-term endeavour!

Spaced repetition software

Spaced repetition as implemented in a computer application is often called SRS, short for spaced repetition software. While the spacing effect is not limited to flashcards, vocabulary or even language learning, software makes using spaced repetition practical.

Let’s explore why!

Here is a stylised version of the forgetting curve, which has been researched for well over a century. It’s borrowed from Skritter, which is one example of SRS.

What does this image show?

The grey dotted line, the forgetting curve, shows how much you will remember without any reviewing at all. As we all know, repetition is the mother of learning, so if you don’t review, you will forget.

The solid teal line shows what happens if you review what you have learnt before you forget it, with increasing intervals between each review.

The increasing intervals are important because vocabulary you know well needs to be reviewed less often, freeing up time to learn new characters and words.

The reason software is necessary here is that when you learn thousands of characters and words, it becomes prohibitively time-consuming to keep track of them individually by hand.

The alternative is to sort paper flashcards into shoeboxes with different intervals on them (a Leitner system). This certainly works for a low number of flashcards, but quickly becomes impractical.

Digital flashcards also have many other benefits, including portability, backups, shareability, study statistics, multimedia use and much more.

Different kinds of spaced repetition

Before we go into practical details on how to use spaced repetition software to learn Chinese vocabulary, it’s worth noting that spaced repetition is not limited to flashcards.

While flashcards are highly efficient in combination with spaced repetition, they are also somewhat artificial and not every student’s idea of fun.

When you think about it, though, reading is also a kind of spaced repetition. If you read a lot, you encounter words repeatedly, spread out over time. Of course, it’s not according to a carefully designed algorithm, and the repetitions are not always spaced, but they often are.

The more you read, the better, and the more you understand what you read, the better, too. The same can be said about listening.

An introduction to extensive reading for Chinese learners

Reading and listening also have significant benefits over flashcards in other areas, such as when it comes to learning how words are used, understanding grammar and building a feel for how the language works.

One advantage that spaced repetition software has over reading and listening is that it’s systematic. With SRS, you will review everything according to an algorithm. You will still forget some things, but not because they never showed up or were neglected.

When reading and listening, which characters and words you see is, for practical purposes, random. You might see a certain word ten times in one day, but then not see it for three months. With enough input, this needn’t be a problem, but it can be.

Here is a simulation of spaced repetition software, compared with more haphazard reviewing:

Spaced repetition and flashcards for Chinese learners

If you want to commit the basic meaning of characters and words, along with how they are written, without spending more time than you have to, nothing beats spaced repetition with flashcards.

I remember what it was like to start using SRS halfway through my first semester of Chinese. I went from struggling to keep track of all the characters and words we learnt in class to easily nailing every single test we had. And I spent less time on vocabulary learning, not more!

Before we wrap up this article, let’s have a look at how you can do the same to boost your learning.

Getting started with SRS as a learner of Chinese

My goal in this section is to get you started, not to explain the ins and outs of flashcard design, in-depth comparisons between different SRS or how to configure them properly.

Here’s what I think you should do:

• Consider what you want to use SRS for. Obvious candidates are writing Chinese characters, reading characters and words, and understanding spoken words. You might want to do one or all three, depending on your learning situation.
• Choose a solution that supports your goal. For a free solution with lots of room to tinker, go with Ank (note: single purchase on iOS). For flashcards and spaced repetition integrated with a great dictionary, use Pleco. And if you care about handwriting, choose Skritter (I have used Skritter for more than a decade and also work for them; see my review for details). I recommend against using built-in SRS in apps which aren’t truly built for SRS (that is, get an app that is focused on spaced repetition, not a movie-learning app with SRS tacked onto it).
• Start with only one card type (or perhaps two). If you want to learn to read Chinese, start with reading cards only (Chinese characters on the front, meaning on the back). If you want to focus on listening, do the same, but with audio on the front instead (yes, you can have audio on digital flashcards). If you care about handwriting, make sure your cards are set up so you write the characters from memory without seeing the answer when you write.
• Start with default settings and tweak as you go along. Most apps have decent settings out of the box. There is little point in agonising over the perfect settings, and you’re better off just taking that time to learn more vocabulary instead.
• Use SRS to review vocabulary, not to learn completely new characters and words. It’s called spaced repetition software for a reason. Don’t import a huge list of vocabulary to your app and start hacking away at it. Instead, read and listen more and add flashcards for characters and words you seem to encounter often. Learning words from lists is, generally speaking, not a good idea.

Should you learn Chinese vocabulary from lists?

Spaced repetition software: A few tips along the way

Here are some tips and tricks that will help you succeed with using spaced repetition software for learning Chinese.

• Test one thing per card. Test reading or listening, not both. Test handwriting or tones, not both. If you test more than one thing, scheduling will be weird because you can’t tell the program that you know half the answer.
• Add only words you really want to learn. It’s easy to go overboard with SRS and add dozens, hundreds or even thousands of words quickly. Don’t do this. Most of your vocabulary should come from reading and listening, or from communicative needs, not from lists you find online.
• Monitor how much time you spend on flashcards. As mentioned earlier, flashcards should make up a small part of your total study time. In Paul Nation’s four-strands model, language-focused learning, including flashcards but also explicit learning of grammar, pronunciation and more, should take up no more than 25% of your time. Flashcards probably shouldn’t take up more than 10-15%.
• Adopt an active attitude toward your flashcards. Only add things you really want to learn, delete things you no longer think are interesting or useful, and edit entries that don’t match your requirements. Cultivate your flashcard garden (or burn it down and start from scratch if you have to).
• Don’t let the allure of measurable progress fool you. Just because progress with SRS and flashcards is easier to measure compared to more hazy things like reading ability or listening comprehension, it doesn’t mean flashcards are more important. I wrote more about this here: Measuring your language learning is a double-edged sword.

Cultivate your Chinese flashcard garden… or burn it down and start afresh

Conclusion: SRS is not a silver bullet, but it’s still awesome

Forgetting is part of learning, but with spaced repetition, you can make that process work for you instead of against you.

By reviewing information at just the right time, you strengthen your memory and dramatically reduce the frustration of relearning what you already studied.

This is extremely useful for some aspects of learning Chinese, such as handwriting characters, but clearly not enough in itself in most cases.

The key is to see spaced repetition as one part of a balanced approach to learning Chinese. Combine it with regular reading, listening and real-world communication.

SRS won’t make you fluent or literate, but it will give you a strong foundation to build on without taking too much time away from the practice that really matters.

More about spaced repetition software on Hacking Chinese

Editor’s note: This article, originally published in 2010, was rewritten and republished in February 2026.