The Rule of 2 – How Many Words You Should Know (For Every Language Level)

Share the knowledge!
Share the knowledge!

I love words.

They are like tiny, beautiful puzzle pieces.

Choose the right ones and you can assemble beautiful and meaningful sentences. Sentences which convey your thoughts with surgical precision.

Choose the wrong ones and you will get a stinky bag of confusion.

But there is a lot of confusion around how big your vocabulary should be for each level.

I have heard dozens of different versions.

That’s why I decided to come up with an easy rule on how to remember it.


The Rule of 2 – How Many Words You Need To Know For Every Language Level

But first things first.

If you have no idea what a language level is, refer to Common European Framework of Reference For Language Learning.

Now back to the rule! It is as simple it gets.

The number of words needed to advance to every level doubles.


Language LevelNumber of Base Words Needed

Feel free to add or deduct 20% of the given values.

Why 20%? Because words you choose to learn matter that much! If you were to concentrate on words from frequency list, you would definitely have to deduct 20% on higher levels (B1-C2).

However, if you, for some reason, started learning names of trees or birds, you would have to add 20% on the said levels.

What Words Mean?

It definitely needs some clarification since this term has changed its meaning in Linguistics in a last few decades.

In the past “a base word” was the base word itself and all its inflected forms. For example “tough”, “toughen” and “toughness” used to be treated as 3 words.

Nowadays “a base word” indicates “the word family” and consists of the base word and its inflected forms and derivations.

According to a renowned linguistic researcher Paul Nation, if you use the 1.6 factor to base words, you should get (more less) the number of “separate” words (i.e. inflected words).


“But why do I need to know it?”

A fair question I guess. It’s not a fun fact which you can rub in somebody’s face.

There are two good reasons:

  • Vocabulary size is a good indicator of your current level


The number of words you know is one of the most reliable indicators of your level. If you track the size of your vocabulary, you should be able to tell (more less) what level you’re on.

Assuming of course that you learn the right words. Memorizing names of plants won’t get you far!

  • Vocabulary size can be your milestone


Not knowing where you are heading can be frightening. It’s like straying in the fog. You don’t know what lies around the corner.

Knowing your goal can give you a sense of direction. Even if you fall,  it will be on a pile of cushions, not the sharp rocks.


4 Most Important Vocabulary Milestones In Language Learning
Photo by: John Spooner

Photo by: John Spooner


Just in case you wonder – the following rules stand true for most of the languages. Be it Asian or European. But since languages tend to differ from each other quite a bit, please take it with a grain of salt and use these calculations only as a landmark.


  • 1000 words

1000 words allow you to understand about 80% of the language which surrounds you, as long as it is not too specialized.

In theory, it sounds great. JUST 1000 words and you understand that much! Unfortunately, the remaining 20% is what really matters.

Just look at this sentence:

“I went to the … to buy …. but they told me that they can’t … .’

Sure, you understand a lot of words. But does it really help?


  • 3000 words

3000 words allow you to understand about 95% of most ordinary texts (Hazenberg and Hulstijn, 1996).

It seems like a lot. Sure, on this level, you will be able to hold a decent conversation. You will also be able to get the general ideas and concepts of most of the articles.

BUT…general comprehension is not the same as full comprehension, as it involves some guessing.

Still, there is no shortage of enthusiasts who claim that such level is high enough to start picking up new words from context. However, researchers tend to disagree and say that the “magical” number of words which allows learning from the context is….(drum roll)

  • 5000 words

5000 words allow you to understand about 98% of most ordinary texts (Nation (1990) and Laufer (1997)).  Such a vocabulary size warrants also accurate contextual guessing  (Coady et al., 1993; Hirsh & Nation, 1992; Laufer, 1997).

It means that you can function surrounded by this language without bigger problems. Sure, you will struggle if you want to formulate your thoughts really precisely, or when you encounter specialized vocabulary.

But other than that, you will be fine.

  • 10000 words

10000 words allow you to understand about 99% of most texts (Nation (1990) and Laufer (1997)).

This is the pinnacle of language learning. A counterpart of having the vocabulary of a college graduate.

With that many words, you can express yourself with amazing precision and pass for a native speaker if your accent is good enough.

This is the minimal goal for every language I learn. It makes me feel like a citizen of a given country.

If you want to download frequency lists for your target language, visit this website.


Final Thoughts

Knowing how many words you need to know to get to C1 level definitely gives you some perspective on how much effort it actually takes to achieve this monstrous goal.

I’m writing this because many of us get depressed after seeing dozens of videos on YT of people speaking or claiming to speak 10 or 20 languages.

But the truth is that there is clearly a yawning gap between being good and being great at a language (or anything else for that matter).

Any person who has truly mastered a language (i.e. achieved C1/ C2 level) could have learnt 2-4 languages to B2 level or 4-8 languages to A2 level in that time

Remember it the next time gloomy thoughts start creeping up on you, my friend.


  • My friend,

    This is an amazing article you nailed it really! Keep up the great work. Thank you.


  • You’ve inspired me to reflect on MY vocabulary size)))

  • go raibh maith agat.

  • Hi Bartosz, One of the best, most practical and inspiring articles I’ve read on the topic. Thanks for posting it.

  • That’s amazing because I was looking for this very information last week and I couldn’t find anything interesting. This article is perfect. I share it. 🙂
    I agree that there’s a gap between B2 and C1. I lived in Brazil 7 months to learn Portguese and discover Brazilian culture and I didn’t really study there, which was bad. I think at that time I knew 5000 words. I was frustrated because I didn’t reach the level I wanted and have the hability to speak fluently though I could understand them pretty well and make some grammaticaly correct sentences.
    Now, i am in Argentina, I want to learn Spanish and before to read your article I estimated the number of words I needed as more or less 10 000. Know, I have the same level in Spanish that I had in Portuguese, and I know that with little work I can reach a good C1 or C2 in few month, because I am not interested in speaking well, I want to speak like a citizen in every language I know. 🙂

    • Hello!

      I know the pain – I also couldn’t find any good article about this topic! 🙂

      Learning 10k words takes some time but it’s time well spent!
      Good luck with your mission! I’m sure you will succeed! 🙂

  • Have you read this article?:
    Could you send some links to the research articles you mentioned? They are a bit tricky to find.

    Thank you!

  • I loved this post. Thanks for the great explanantion. I am learning Ukrainian, so there arent any common european framework tests that I could find (for free at least). This give me a SMART goal now. Really appreciate this post.

  • Raymond John Edwards

    Hang on…. English has over one million words, divide by four to approximate the number of base words, that’s 250 thousand. Are you seriously saying that you have mastered a language after learning 4% of these? I have taught English for many years and in my opinion this is nonsense.

    • Hi Raymond!

      The number of words in English vary significantly. Frankly, it depends on the source of information.
      Secondly, yes this is what both research and my personal experience says.
      I can only assume, by your name, that English is your native tongue and you haven’t really learnt any other language to C1 level.
      If you did, you would definitely notice that 10k words are more than enough to function freely within boundaries of basically any language.
      I don’t mean to offend you or be snarky in any way, just to be clear.
      I guess that the potential misunderstanding might be also a result of different definition of “mastery”.
      What is yours?

      Tank you for your comment Raymond!

  • Could you precise how did come up with the specific number of words for each language level from CEFRL ? It is nowhere to be found in the wikipedia article. Thanks.

    • Bartosz Czekala

      Basically, it’s the mix of my own calculations which are based on CEFRL.
      CEFRL specifies in a quite detailed way, what is the expected level of comprehension on each of the levels.
      I cross-referenced this info with the expected level of understanding for each of the aforementioned milestones.
      I also used some papers to back-up my data. So yeah, that’s pretty much it 🙂 Hope that helped!

  • I haven’t read any article of this kind before. It’s very interesting and really encourages me to learn more and more. Besides you helped me to choose the right direction in improving my skills. Thanks a lot.

  • Hi Bartosz, I would like to congratulate you for the very interesting article, method and calculations!
    I’ve been looking for such a piece of info for quite a few days and many different word combinations on Google were tried out to finally get me here.
    Knowing exactly the number of words one should master to get to a milestone like C1 level is of great help for using tools such as Ankidroid, where you have various lists from 1K to 10K to choose from, what makes you a bit confused about whether all of those words in the long lists would be needed, cause else you’d be fine hitting a shorter list and the pursuing a proficiency test.
    Now thanks to your article I’ve found out that much work has to be done for me to reach C1 level on German. Keep up the good articles! Thank you!

    • Hi Rodolfo! I’m beyond happy that you enjoyed it. Thank you for your comment and good luck with your learning! 🙂

  • Adalberto da Silva

    Hello Bartosz.
    i’ve learned at high cost that it is this simple: if you try to read interviews with models or soccer-players and it seems toooo foreigner Gotta dedicate good time to learn more words.
    Even germans say gernan is a straight-forward language. Nein! JorgeLuisBorges in Ode to German Language mentions german dictionaries that never get it right. They don’t help much.
    i may be able to know passive-wise about 5,000 words in german. Man, still far. But as Michael Erard tweeted(google)”Everybody loves a polyglot.” Worth taking the hard road.
    Bye Tchau Ciao Adios À bien-tôt (and hopefully eon(en?) schön Tag: Tschús!)

  • I happy to read your article and I see it’s very important, thank you.

  • I knew one guy (during my studies) who had many exercise books full of english words. It was his method to improve the vocabulary size. His name is Bartosz Czekała, I’m so proud of you 😉 On the other hand, I work on my vocabulary size now and started writing new words into.. exercise book. Test showed the knowledge of 7,1k words, so much more work to do. Have a nice day 🙂

    • Well, my methods back then were pretty ineffective! 🙂 IT’s a great result! You are definitely on your way to achieve full fluency!
      Thank you for your comment Pawel! 🙂

  • esperanza salazar

    HI! I´m wondering where did you get the info from? I mean, the number of words for each level.

    • Bartosz Czekala

      Basically, it’s the mix of my own calculations which are based on CEFRL.
      CEFRL specifies in a quite detailed way, what is the expected level of comprehension on each of the levels.
      I cross-referenced this info with the expected level of understanding for each of the aforementioned milestones.
      I also used some papers to back-up my data. So yeah, that’s pretty much it 🙂 Hope that helped!

  • Neatly done, mate! I have been dreaming of inventing a machine that would be able to “measure”/count/?/ our vocabular capacity. Something like a speedometer, thermometer, etc .. Maybe one day in future?:) Keep rocking, bud

  • Zastanawiam się, czy tu “wolno” pisać po polsku? 😉 OK ok, for other users reading… – how many languages do you know with 10k words if I may ask? How long did it take you? I have just started learning Spanish, today, as of 3.30 pm. I “need” it to… teach it to my kids. They are homeschooled and we are not awfully rich to pay for so many courses. I know English well enough, and German, Italian and French just a little I guess, but I “forgot” them sort of. Stopped using them. So I decided to learn something new this time, and that’s how I got here, to this site. And it’s inspiring I must say, and quite interesting. Keep up the good work!

    • Wszystko wolno! 🙂

      6 out of 8. Somewhere next year I will achieve this goal for remaining 2 (SPanish, French).
      It depends on a language. The quickest I have heard a 10k mark was for Swedish, Took less than a year,=.
      Hope you succeed! 🙂 Drop me a message if you need some help 🙂

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