How Many Words Do You Need to Know to Become Fluent in a Language?

By OptiLingo

How many words do you need to know to become fluent in a language? Some experts will tell you that’s not the right question to ask. But it’s a question that’s definitely worth examining.

Although it is impossible to answer the question with an exact number, many language learners believe that once they have acquired a certain number of words, they can consider themselves fluent.

If only it were that simple. Counting words is not an effective way to evaluate fluency. There are several reasons for this.

First: It is impossible to come up with an exact number of words that demonstrates fluency.
Second: Language experts disagree about how to measure vocabulary size.
Third: When it comes to learning a language, all words are not the same.

Some words are more valuable for people to learn than others, and the order in which they learn words matters.

In this blog post, we are going to look at the reasons why it is so difficult to come up with an exact word count. We’re also going to consider other methods of evaluating proficiency while examining the relationship between learning individual words and learning a whole new language.

Our ultimate goal here is to discover the best way to learn a new language and how to measure our progress. To do so, we will discuss different approaches language experts use to try to count the number of words in people’s vocabularies.

We will then consider the usefulness of looking at ranges of words, even if it is not possible to come up with precise numbers, and we will contemplate a classification scheme based on those ranges. Finally, we will discuss how people can accelerate their language learning by choosing which words to learn before others.

First, we need to deal with the question of how many words you need to know to be proficient in a language. Teaser Alert – Not only do experts disagree, they don’t even share a consensus on what constitutes a word or on what it means to know a word.

Obviously we need to unpack this question and scrutinize its parts to understand it better.

What is a Word?

“What is a word?” is a more complex question than it might appear at first glance. You might assume everyone means the same thing when they talk about a “word,” but that turns out not to be the case at all.

Language experts sharply disagree with each other about the number of words people have in their vocabularies. For example, one expert says the average native English speaker who is a high school graduate knows at least 35,000 words. Another expert says the average native English speaker who is more highly educated has a vocabulary of 10,000 words.

It doesn’t make sense that people with more education would have smaller vocabularies than people with less education. Where does this discrepancy come from?

The difference in the numbers is the result of the way experts measure what they are studying. They are actually measuring different things. They don’t agree on the definition of “word” or the definition of “know.” So it is not surprising they come up with such different answers to questions about how many words people know.

Some experts count every form of a word as a separate word. For example, they count each form of the verb “to see” separately. By this measurement, “to see,” “see,” “sees,” “seeing,” “saw” and “seen” would be considered six individual words. These experts apply the same logic to nouns, counting “cat” and “cats” as two separate words.

Other experts count only the root word and not its different forms. As a result, they come up with much smaller numbers. These experts count “to see,” “see,” “sees,” “seeing,” “saw,” and “seen” as only one word because they are all forms of “to see.” They also consider “cat” and “cats” as a single word because the singular and plural are forms of the same root noun.

Their thinking is that when people learn a root word, such as “to see” or “cat,” they are learning a new word for the first time. However, when the same people then learn different forms of the root word, such as “seeing” or “cats,” that should be considered an addition to their knowledge of grammar instead of an expansion of their store of new words.

After all, these experts say, this is how we learn languages. First we learn one form of a word. Then, as we learn more about the structure of the language, we can generalize the use of the word to other situations, using its other forms.

When evaluating the number of words in people’s vocabularies, the experts who count every form of a word will come up with a much higher word count than will the experts who count only the root forms. And that’s the case even when both sets of experts are studying the same language and the same groups of people.

Which standard of measurement should you use? Neither one is right or wrong. They are both valid ways of measuring the size of people’s vocabularies. What is important when you compare individuals or groups to each other is that you pick one method of measurement and then use it consistently in order to have meaningful results.

What Does It Mean to “Know” a Word?

Again, let’s go back to our original question: How many words do you need to know to become fluent in a language? The next thing we need to consider is what it means to “know” a word.

People who study languages make a distinction between what they call “active vocabulary” and “passive vocabulary.” Some think people “know” a word only if it is in their active vocabulary, while others believe people “know” all the words in their active and passive vocabularies combined.

A word is in your active vocabulary if you can remember it quickly and use it without hesitation in your thoughts, when you talk and when you write. A passive vocabulary word is one you can recognize and understand, more or less, when you happen to hear it or see it, but you can’t easily remember the word and are not comfortable using it in conversation. For both native and non-native speakers, the number of words in passive vocabularies is usually several times larger than the number of words in active vocabularies.

People will generally absorb a new word into their passive vocabularies after they see or hear it the first few times. Then, as they encounter the word more often and as they better understand its context and different meanings, it becomes part of their active vocabularies. One of the best ways to expand your knowledge of a language is to move words up from your passive to your active vocabulary.

Vocabulary Ranges

Now that we have seen why language experts differ so widely when they count words in people’s vocabularies, we can return to our original question about how many words you need to know to be considered fluent. For the purpose of this discussion, we will measure vocabulary by counting only root words and not their different forms, and by counting only the words in people’s active vocabularies.

This is the approach taken by the Common European Framework of Reference for Languages (CEFR), which has become the de facto standard for grading an individual’s language proficiency.

The CEFR is a current guideline used to describe achievements of learners of foreign languages across Europe and, increasingly, in other countries. It was put together by the Council of Europe as the main part of a project called “Language Learning for European Citizenship” between 1989 and 1996. Its main aim is to provide a method of learning, teaching and assessing which applies to all languages in Europe. The six reference levels (see below) are becoming widely accepted as the de facto standard for grading an individual’s language proficiency.

Using this method of measurement, we can sort people based on their language fluency into six groups or levels:

Learn the Right Words in the Right Order

A great way to accelerate your language learning is to pay attention to which words you should learn first, instead of trying to learn as many new words as fast as you can. Focus first on learning the words that will benefit you the most.

For example, in English, about 95 percent of everyday conversations draw from a store of only 3,000 words. Learning those 3,000 words first will be far more efficient than learning 3,000 words at random. By starting with a list of the most commonly used words, you can take a shortcut toward being able to carry on everyday conversations.

To optimize learning, someone studying English should learn to recognize the most high-volume words, such as “the,” “to be,” “and,” “have” and “you” before they tackle less common vocabulary words. Make sure you learn the basics before going on to study the names of animals and plants, current slang expressions, or other words that are not as essential to basic conversational skills.

The Pareto Principle

Vilfredo Federico Damaso Pareto was an Italian philosopher and engineer known for documenting the 80/20 rule, which is now often called the “Pareto Principle” in his honor. Pareto discovered that in many situations, 80 percent of the effects come from only 20 percent of the causes.

The Pareto Principle is useful in many fields because it helps people focus on the actions they can take that will have the greatest impact. For example, software developers find that fixing 20 percent of the bugs in a software product can eliminate 80 percent of the product’s defects. The trick is to concentrate on the correct 20 percent. In the software example, that means focusing on fixing the bugs that users report most often.

Traffic patterns also follow the Pareto Principle. In many locations, 80 percent of the traffic will occur during 20 percent of any given time period. This is useful information for city planners, who can focus their efforts to manage traffic where they will do the most good.

For language learners, this means most of your progress will come from targeted learning. While this may not break down exactly to 80 and 20 percent, the general rule is useful here.

That’s why many people often begin their language studies by attempting to memorize high frequency words. Without getting into the pros and cons of this approach, adherents will often focus on the first 500–1,000 most frequently used vocabulary words in their target language.

If this is an approach you’re considering, give careful thought to where you pick up your vocabulary lists and how they were created. Going back to our exploration of “what is a word,” you may want to consider how you choose to study definitions.

You don’t need to memorize every definition of the words you are learning. That would be very time-consuming because some common words have several alternative definitions not commonly used.

(For example, in English, the word “murder” normally means “to kill.” It is a word one often encounters in news reports. An alternative definition is “a flock of crows.” This secondary definition is not commonly known among native speakers, let alone students.)

Instead, it is far more efficient to learn only a few of the most common definitions – the ones you are likely to need in ordinary conversations. Then, with experience, you will naturally learn more when you hear the words used in different contexts. In that way, through exposure to the language over time, you will assimilate the language, learning it in a natural way.

If you focus on learning words you will use the most and on learning the most useful definitions, you will be able to learn the language far more efficiently than if you tried to learn everything at random.


There is no precise number that will answer the question of how many words you need to know to become fluent in a new language. In part, that is because language scholars use different measurements when they count words and apply different standards to evaluate what it means to know a word.

Nevertheless, it is useful to consider how many words people know if you look at ranges, rather than at exact numbers. It then becomes possible to group people by their language proficiency according to a rough estimate of the number of words they know.

People who know 250 to 500 words are beginners. Those who know 1,000 to 3,000 words can carry on everyday conversations. Knowing 4,000 to 10,000 words makes people advanced language users, while knowing more than 10,000 words puts them at the fluent or native-speaker levels.

When it comes to learning a language, all words are not equal. Learning some types of words will accelerate your progress more quickly than learning other types of words. To be most effective in learning a language, focus on the most common words in that language before starting to study more specialized vocabularies. And learn the most common definitions first instead of trying to memorize every definition.

The Pareto Principle, which says 80 percent of effects come from 20 percent of causes, applies in a general way to learning a new language. That is, you will progress the fastest if you start by spending your time learning what you can use right away. If instead you try to read a dictionary from cover to cover, learning every word and every definition in the language, much of your effort will be inefficient at best and wasted at worst.

Learning the most common words and definitions puts you in a position where you can start assimilating the language in a natural way. The more you hear and read words in the language, the more you will understand new words and new meanings from the context they are used in and from other relevant cues. This is similar to the way you learned your first language as a child. The more you expose yourself to your new language, the more fluent you will become.

You don’t need to count the number of words you learn in order to become fluent. Instead, put your time and effort where they will do the most good. Speed up your language learning by focusing on the most commonly used words, then let your natural language-learning ability take over.

This combination of targeted studying and assimilating language by experience is the most powerful and efficient way to master a new language.