Lose and loose differ by a single o, but they mean completely different things, and one of them isn't even a verb most of the time.

The short answer #

Word Meaning Example
lose (verb) to misplace, or to not win Don't lose your keys.
loose (adjective) not tight, not fixed This shirt is loose.

Lose #

Lose rhymes with choose. It's a verb.

  • I always lose my headphones.
  • We might lose the game.
  • You'll lose progress if you close the app.

Past tense: lost. I lost my wallet.

Loose #

Loose rhymes with goose. It usually describes something that isn't tight or secure.

  • The screw is loose.
  • She wore her hair loose.
  • The dog got loose again.

A spelling trick #

Loose has an extra o, like it has extra room. Loose clothes have extra space; lose has lost an o.

Common mistakes #

Wrong Right
I don't want to loose you. I don't want to lose you.
Did you loose weight? Did you lose weight?
My tooth is lose. My tooth is loose.

Never mix them up again #

Because both spellings are real words, spell check won't warn you. AI Grammar Checker reads the sentence and fixes lose and loose in context.