Each picks out the members of a group one at a time; every sweeps the whole group together with no exceptions. Compare "the nurse spoke to each patient" (separately, one after another) with "every patient was screened" (all of them, as a group). Each works with as few as two things; every needs at least three.
The core difference
Both words point at all the members of a group, but they look at them from different angles. Each zooms in: it takes the members one at a time. Every pulls back: it takes them all at once and stresses that none is left out.
That is why "I read each page carefully" suggests a slow trip through the pages one by one, while "I read every page" simply reports that nothing was skipped.
How to use each
- With two things: She held a suitcase in each hand. ("every hand" is wrong here.)
- On its own, as a pronoun: Each of the applicants was interviewed twice.
- After the subject: They each brought something to the picnic.
- After a plural noun and number: The tickets cost £15 each.
How to use every
- For three or more, viewed as a whole: Every seat in the theatre was taken.
- With words that soften or strengthen it: almost every, nearly every, practically every, virtually every. Each never takes these.
- For regular intervals: The bus leaves every twenty minutes. She visits every other weekend.
- Every cannot stand alone. You need every one: Every one of the windows was cracked.
A test you can run
Try slipping "separately, one at a time" into your sentence. If it still makes sense, each is the better fit: The judge questioned each witness (one at a time). Now try "all of them, without exception". If that is the point you are making, use every: Every witness was questioned (no exceptions).
Second check: if the word almost would fit in front, only every works. "Almost every seat" is fine; "almost each seat" is not.
Where people slip
Both take a singular verb, which trips up careful writers: it is each of the reports is due and every report is due, not are. The plural noun sitting next to the verb creates the pull, but the subject is still each.
In many everyday sentences the two are genuinely interchangeable — each time and every time both work, and nobody will misunderstand you either way. The difference only really bites when you are contrasting individuals with a whole, or when the group has just two members.
Frequently Asked Questions
Is it "each of us has" or "each of us have"?
Has. Each is singular, so it takes a singular verb even when "of us" follows: "Each of us has a copy of the key." The same applies to "each of the students was late".
Can I say "every two people"?
Yes, when you mean a repeating interval: "One in every two people owns a smartphone." That is different from "each of the two people", which points at both individuals separately.
Which is right: "each and every"?
It is grammatical but redundant — it says the same thing twice for emphasis. It works in speech and persuasive writing, but in plain prose one word alone is stronger.