Use to for movement or direction and in front of a verb (go to school, want to leave). Use too when you mean also or excessively (me too, too hot). Use two only for the number 2 (two dogs). All three sound identical, but they are never interchangeable in writing.
These three are homophones — they're all pronounced roughly the same way ("too"), which is exactly why they get muddled on the page. In speech nobody notices; in writing, mixing them up is one of the most common slips in English. The good news is that each word has a narrow, well-defined job, so once you know the three roles you'll never have to guess again.
"To" is the workhorse of the three, and it does two main jobs:
You'll also see it in countless fixed phrases: according to, due to, next to, up to you, talk to me. When the word isn't a number and doesn't mean "also" or "excessively," plain "to" is the safe default.
"Too" is an adverb with two senses, and helpfully both are about more:
Notice that "too" carries an extra "o" — and it always signals something extra: an added item, or more of something than you want.
"Two" only ever means the number 2. Nothing else. I have two sisters, a table for two, cut it in two. The silent "w" links it to its number-two relatives: twin, twice, twenty, between, twofold. If you can't swap in the digit "2," you don't want "two."
Side by side, the difference is obvious:
English loves pairing "too" with "to": too tired to think, too good to be true, too far to walk. Here "too" means excessively and "to" introduces the verb. They are two different words doing two different jobs in the same phrase — spell them differently.
Yes, "two" and "too" can legitimately sit right next to each other: You've poured two too many. That means two more than you should have. It looks like a typo, but it's perfectly correct — the number followed by the "excessively" adverb.
When "too" means also, the comma is optional. I want dessert too and I want dessert, too are both fine, and modern writing tends to drop it. Do use commas when "too" interrupts mid-sentence for emphasis: I, too, was surprised.
When you're mid-sentence and can't decide, ask three questions in order:
Nine times out of ten you'll settle it on the first or second question.
Because "to" is both a preposition and the infinitive marker, it attracts two stubborn "rules" that aren't real rules at all:
These affect where "to" sits in a sentence, but they never change which of the three homophones you spell.
Reassuringly, none that matters. "To," "too," and "two" are spelled and used identically in American, British, Australian, and every other variety of English. The only faint transatlantic habit is that American style guides have historically been slightly keener on a comma before "too" (I'd like to come, too) — but even that is optional and fading on both sides of the Atlantic. Get the three spellings right and you're correct everywhere.
It's always "me too." Here "too" means "also" or "the same goes for me," and the sense of addition always takes the double-o spelling. "Me to" is incorrect in this phrase. The same rule gives you "you too," "I love you too," and "can we come too" — every one with "too."
Use "too" only when you mean "also" (I'm coming too) or "excessively" (too expensive). If you can swap in "also" or "overly/very" and the sentence still works, spell it "too." For anything showing direction (go to work) or sitting before a verb (want to help), use plain "to" instead.
Link each spelling to a clue. "Too" has an extra O, and it means something extra — also or too much. "Two" shares its "tw" with twin, twice, and twenty, so it's the number. "To" is the plain, general-purpose word left over for directions and verbs. Match the clue to the meaning.
It's "too much." "Too" here means "excessively," and that sense always takes the double-o spelling: too much, too many, too far, too late. "To much" is a common typo but never correct. Quick test: if you could say "excessively" or "overly" instead, you need "too."
Yes. "Two too many" is correct and means two more than you should have, as in "You've had two too many." It looks like a mistake but isn't: "two" is the number and "too" means "excessively." Similar correct phrasing includes "two too few" and "two too big."
