Good and well are both positive words, but they do different jobs in a sentence.

The short answer #

  • Good is an adjective: it describes a noun. a good idea
  • Well is usually an adverb: it describes a verb, telling you how something is done. She writes well.

Good describes things #

  • That's a good question.
  • The app has good reviews.
  • This coffee tastes good.

After verbs of the senses and be, seem, look, and feel, use good, because you're describing the subject, not the action: The plan sounds good.

Well describes actions #

  • You did well on the test.
  • He speaks English well.
  • The meeting went well.

"I'm good" vs. "I'm well" #

Both are correct, with slightly different meanings.

  • I'm well. uses well as an adjective meaning healthy. It's a little more formal.
  • I'm good. means you're fine or in a good mood. It's very common in conversation.

Common mistakes #

Wrong Right
You did good. You did well.
She sings really good. She sings really well.
This pizza smells well. This pizza smells good.

Quick test #

Ask: Am I describing a thing, or how something is done? A thing takes good; an action takes well.

Let AI polish it #

AI Grammar Checker corrects good and well and other adjective–adverb mix-ups so your writing sounds natural.