How Many Words Are in the English Language?

There’s no exact count of English words, because the language keeps growing and there’s no agreed rule for what counts as a single word. Merriam-Webster cites an estimate of roughly 1 million words, a figure that includes huge numbers of chemical and scientific names, and notes that some linguists think it could be off by a quarter-million (Merriam-Webster). The biggest dictionaries hold about half that. The Oxford English Dictionary has over 500,000 entries (OED), and Merriam-Webster Unabridged has over 476,000 (Merriam-Webster Unabridged). A typical person knows far fewer: about 42,000 base words for an average 20-year-old native speaker of American English (Brysbaert et al., 2016).

Why there’s no single number

Merriam-Webster’s editors list several problems with counting (Merriam-Webster):

• Words like cannoli and teriyaki came from other languages and became English through use, so the language has no fixed border.
• Drive, drives and drove could be counted as one word or three.
• Webster’s Third New International Dictionary has twelve separate entries spelled “post,” each with a different part of speech or origin.
• “Port of call” has its own entry, even though port, of and call are each entered separately.

That million-word estimate also sweeps in the names of chemicals and other scientific things, many of which are so far from everyday English that they don’t appear even in an unabridged dictionary (Merriam-Webster). Chemical names are also why the longest string of letters in English doesn’t count as a dictionary word, as we explain in our guide to the longest word in English.

What dictionaries say about their own size

Each dictionary counts in its own way (entries, definitions or word forms), so these numbers aren’t a like-for-like comparison.

Dictionary	What’s counted	Figure	Source
Oxford English Dictionary (online)	Entries	Over 500,000	OED
Oxford English Dictionary (online)	Definitions	Almost 850,000	OED
OED Second Edition (1989)	Entries	291,500	OED
OED Second Edition (1989)	Word forms defined or illustrated	615,100	OED
OED First Edition (1884 to 1928)	Entries	252,200	OED
Merriam-Webster Unabridged	Entries	Over 476,000	Merriam-Webster
Merriam-Webster’s Collegiate, Eleventh Edition	Definitions	225,000	Merriam-Webster

• The OED is a historical dictionary. It traces words back as far as the 11th century through 3.5 million quotations (OED), so it includes words nobody uses anymore. Its Second Edition had 47,100 main entries for obsolete words (OED Editions).
• Merriam-Webster gives two figures for its unabridged dictionary. Its FAQ says Webster’s Third plus its 1993 Addenda Section has “some 470,000 entries” (Merriam-Webster). Its current product page, which describes an updated addenda section, says over 476,000 (Merriam-Webster shop), and so does the Unabridged’s help page (Merriam-Webster Unabridged). We use 476,000, the figure on Merriam-Webster’s current pages.
• The same Merriam-Webster FAQ says the OED’s Second Edition reports a similar number, around 470,000. The OED’s own published figures for that edition are 291,500 entries and 615,100 word forms (OED Editions). Neither page explains the gap, so for the OED we go with the OED’s own numbers.
• Merriam-Webster announced its Collegiate Dictionary, Twelfth Edition in September 2025 with a release date of November 18, 2025. It’s the first new edition since 2003 and adds over 5,000 new words plus 1,000 new phrases and idioms (Merriam-Webster press release). The announcement doesn’t give a total entry count.

How a word gets into the dictionary

Both publishers decide based on evidence of how people actually use a word. Merriam-Webster says no committee or advocacy is involved (Merriam-Webster).

At Merriam-Webster, most editors spend an hour or two a day reading books, newspapers, magazines and online publications, marking new words and new uses of old ones. Each example becomes a citation: the word, the sentence it appeared in, and where it came from (Merriam-Webster). The citation files go back to the 1880s, and the help page puts them at 15.7 million examples (Merriam-Webster help), while Merriam-Webster’s article on the process, last updated in 2024, says nearly 17 million (Merriam-Webster).

To get in, a word needs (Merriam-Webster; Merriam-Webster help):

• frequent use over time, so a fad that comes and goes won’t make it
• widespread use, so that an average adult is likely to run into it
• meaningful use, so people use it to mean something and not just as an example of a long word
• citations from a wide range of publications, not just one source or one field’s jargon

Bigger dictionaries let in more words. The Collegiate has limited space, so a word needs plenty of citations, while the Unabridged has room for words with fewer. Now and then a word qualifies fast, as AIDS did in the 1980s (Merriam-Webster). And many “new” words are new meanings of old ones, like the computer senses of mouse and cookie (Merriam-Webster).

At the OED, a word first goes onto a “watch list,” fed by reading programmes, public appeals and automated monitoring of huge databases of real-world English. Editors review thousands of suggestions a year. When a word shows enough sustained, widespread use, an editor researches its history and drafts the entry, which then goes through specialist teams and finally the Chief and Deputy Chief Editors (OED). Finished entries come out in quarterly updates. The September 2026 update added more than 400 new words, phrases and senses, including overnight oats and hot yoga (OED).

How many words are in everyday use

The OED puts each word that’s still in use into a frequency band, from 8 (very common) down to 1 (extremely rare). Modern frequencies come from a 20-billion-word collection of English compiled by Oxford Languages, mainly from online news and covering 2017 to the present. Each band is roughly ten times rarer than the one above it (OED):

Band	Uses per million words	Share of OED entries	Examples
8	Over 1,000	0.02%	the, of, and, be, have (time is the only noun)
7	100 to 1,000	0.18%	man, hand, year, water, good
6	10 to 100	1%	dog, career, headache, red, happy
5	1 to 10	4%	surveillance, penchant, jeopardize
4	0.1 to 1	11%	nutshell, rodeo, egregious
3	0.01 to 0.1	20%	merengue, cutesy, mosey
2	Under 0.01	45%	scintillometer, absterge
1	Extremely rare	18%	grithbreach, zarnich

The OED calls bands 8 to 6 the everyday language, and together they make up about 1.2% of its entries for words still in use. At the other end, it says Band 2 words would be unknown to most people and Band 1 words are unlikely ever to show up in modern text. Those two bands cover 63% of those entries (OED).

For learners, Oxford picks out a smaller core. The Oxford 3000 is a list of 3,000 keywords picked because they’re frequent across many kinds of text, plus some familiar words chosen by a panel of more than 70 teaching and language experts (Oxford Learner’s Dictionaries).

How many words does one person know?

A 2016 study by researchers at Ghent University tested 221,268 people online, showing them a mix of real words and made-up ones. It found (Brysbaert et al., 2016):

• An average 20-year-old native speaker of American English knows about 42,000 lemmas (base words, so “walk” counts once rather than also counting walks and walked), plus about 4,200 expressions whose meaning isn’t obvious from their parts.
• The range runs from about 27,000 lemmas for the lowest 5% to 52,000 for the highest 5%.
• Between ages 20 and 60, the average person picks up about 6,000 more, roughly one new word every two days.
• Knowing a word can be as shallow as knowing that it exists.

The authors note that published estimates of vocabulary size run from under 10,000 to over 200,000, depending on how a word is defined. They say the much higher figures in other publications come from also counting the tens of thousands of inflected forms and names that people learn.