“to” vs. “too”
If the word means "also" or "excessively," write "too" with two o's; for every other use — direction, destination, or before a verb — write plain "to."
to
"To" is a preposition showing direction, destination, or relationship ("go to the store," "give it to her"), and it also marks the infinitive form of a verb ("I want to leave," "to be or not to be"). "To" descends from Old English "tō," a preposition so basic to the grammar that it has stayed in constant service, largely unchanged in its core function, across the entire recorded history of English.
too
"Too" means "also" ("I'm coming too") or "excessively" ("it's too hot outside"), and it's distinguished from "to" by an extra o that has nothing to do with pronunciation and everything to do with keeping the two meanings visually separate on the page. "Too" actually shares the very same Old English root as "to" — it originally was simply an emphatic or stressed pronunciation of "to" in certain contexts, which gradually solidified into its own separate spelling and separate meanings ("also," "excessively") specifically to keep it visually distinct from the unstressed, purely grammatical "to."
The real distinction
"To" and "too" are pronounced identically, so the distinction lives entirely in spelling and function rather than sound. "To" is a grammatical connector — it links a verb to its object or destination, or introduces an infinitive — while "too" is a standalone adverb meaning "also" or "excessively" that could, in most sentences, be replaced by "as well" or "overly" without changing the sentence's structure. Because "too" started life as nothing more than a stressed variant pronunciation of "to," the spelling split into two o's is a comparatively late written convention, not an ancient distinction — which is part of why the words remain identical in pronunciation today even though English writing has fully committed to keeping them visually separate on the page for well over a fourth of the language's recorded history. Professional copyediting checklists frequently list to/too (along with its close relative to/two) among the handful of homophone pairs worth a dedicated final search-and-check pass in any long document, precisely because both words are so frequent that a writer's error rate, even if genuinely low per instance, tends to produce at least one real mistake somewhere across a document of any real length. Because "to" is one of the single most frequent words in the entire English language, even a very low per-instance error rate for this pair can still produce a handful of real mistakes across any sufficiently long piece of writing.
Examples with “to”
- We're driving to the coast this weekend.
- She handed the letter to her manager.
- I need to finish this before noon.
- He decided to apply for the job.
- Send the package to the main office.
- They plan to renovate the kitchen next year.
- Give the documents to the front desk.
- We're hoping to arrive before dark.
Examples with “too”
- I'd like to come too.
- It's too cold to go outside without a coat.
- She thought the price was too high.
- He wants to join the trip too.
- The soup is too salty for my taste.
- We arrived too late for the opening act.
- That's too generous an offer to refuse.
- I'm too tired to keep working tonight.
Memory trick
Picture the extra o in "too" as standing for "one more" — one more thing ("also") or one degree too many ("excessively") — while plain "to" keeps its single o for its plainer job of just pointing somewhere or introducing a verb. A further practical check specifically for the "excessively" sense of "too": if you can insert the word "overly" in its place and the sentence keeps roughly the same meaning ("overly cold" for "too cold"), that confirms you need the two-o spelling rather than the plain preposition. One more sanity check: strike the word out of the sentence altogether — if the remaining sentence is still grammatical, you were almost certainly looking at optional "too," since bare "to" can rarely be deleted without leaving the sentence broken.