Reference

English vocabulary statistics

44 figures on how big a vocabulary is, how big it needs to be, and what each coverage level actually buys a reader. Every number below names the study or organisation that produced it and links somewhere you can read it.

Last verified against sources

Key takeaways

  • An average 20-year-old native speaker of American English knows 42,000 lemmas.
  • By age 60 that median rises to 48,200 lemmas — about one new lemma every two days.
  • Vocabulary size at 20 ranges from 27,000 lemmas for the lowest 5% to 52,000 for the highest 5%.
  • 8,000 word families is the optimal lexical threshold for independent reading in a second language, giving 98% text coverage.
  • 4,000–5,000 word families is the minimal threshold, giving 95% coverage and reading that still needs guidance.
  • The 1,000 most frequent word families cover 78–81% of written English on their own.
  • The second 1,000 word families add only 8–9%, and the tenth to fourteenth add less than 1% combined.
  • Knowing 95% of the words in a text yields roughly 55% comprehension — minimal, not adequate.
  • A 3,000-word vocabulary predicts a reading score of 56%; 5,000 words predicts 70%.
  • Understanding a novel at 98% coverage takes about 9,000 word families; a newspaper takes about 8,000.
  • English is the most studied language in 79% of all countries and ranks #1 in 154 of them.
  • The EF English Proficiency Index 2025 ranks 123 countries and regions using test results from 2.2 million adults.
  • In the national population the study drew on, 9% of learners reach the vocabulary level that predicts functional independence in academic reading.
  • Published thresholds disagree mainly because each study fixes adequate comprehension at a different score — 55%, 70%, or 71%.

How many words does a native English speaker know?

An average 20-year-old native speaker of American English knows 42,000 lemmas, and that figure grows to a median of 48,200 lemmas by age 60.

How many words do you need to know to read English?

8,000 word families is the optimal threshold for reading independently in a second language, and 4,000–5,000 word families is the minimal threshold for reading with guidance.

How much of English do the most frequent words cover?

The 1,000 most frequent word families cover 78–81% of written English, and each additional thousand adds sharply less.

How much comprehension does each coverage level actually buy?

95% coverage yields roughly 55% comprehension, which the research calls minimal rather than adequate; 98% is the level at which reading becomes independent.

Why do studies give different vocabulary thresholds?

The thresholds differ mainly because each study fixes 'adequate comprehension' at a different score — 55%, 70%, and 71% — and the underlying results converge once that is held constant.

  • The studies converge surprisingly well in their results even though, on the surface, they seem to suggest different thresholds; the threshold is contingent on what is considered adequate comprehension.

    Laufer & Ravenhorst-Kalovski, Reading in a Foreign Language 22(1) · 2010

  • Laufer (1992) found a 3,000 word-family vocabulary assures a reading score of 55%, while a score of 70% requires 5,000 word families.

    Laufer (1992) · 1992

    Reported in Laufer & Ravenhorst-Kalovski (2010), p. 18.

  • Hu and Nation (2000) set 'adequate' comprehension at 71%, the average of their two comprehension tests.

    Hu & Nation (2000) · 2000

    Figure quoted in Laufer & Ravenhorst-Kalovski (2010), p. 18. The original paper is open access: Reading in a Foreign Language 13(1), nflrc.hawaii.edu/rfl/item/43.

  • Corpus data in Nation (2006) show 98% coverage is reachable with 5,000 word families plus proper nouns, and 95% coverage with 3,000 plus proper nouns.

    Nation, Canadian Modern Language Review 63(1) · 2006

    Reported in Laufer & Ravenhorst-Kalovski (2010), p. 18.

  • 8,000 to 9,000 word families is the highest estimate for 98% coverage; the same coverage can be reached with a lower vocabulary.

    Laufer & Ravenhorst-Kalovski, Reading in a Foreign Language 22(1) · 2010

What counts as one word in vocabulary research?

Vocabulary studies count word families, lemmas, or tokens, and the three give very different totals for the same learner.

Where in the world is English being studied?

English is the most studied language in 79% of all countries and ranks first in 154 of them.

How is English proficiency measured across countries?

The EF English Proficiency Index 2025 ranks 123 countries and regions using test results from 2.2 million adults.

How this page is sourced

These 44 figures were produced by 9 different studies and organisations, and were read out of 5 openly readable source documents. Every one was taken from the source itself rather than copied from another statistics roundup, and every link was checked to load. Three of the originating papers — Nation (2006) and the Laufer book chapters of 1989 and 1992 — are not open access, so the citation names the paper that produced the figure and links the open-access article that reproduces it, with that indirection stated on the line itself.

You are welcome to cite these figures. Please credit the original study rather than this page, and link here only as a convenience.

Related reading

Build the vocabulary these numbers describe

The figures above agree on the size of the gap: a few thousand word families separate reading that needs help from reading that doesn’t. Vocaby is built to close that gap one word at a time.