Whose and who's sound identical, so they're easy to swap in fast writing. One test tells them apart.

The short answer #

Word Meaning Example
who's who is or who has Who's coming tonight?
whose belonging to whom Whose phone is this?

Who's = who is / who has #

The apostrophe replaces missing letters.

  • Who's ready? → Who is ready?
  • Who's seen my charger? → Who has seen my charger?

Whose = possession #

Whose asks or tells who owns something. Like its, his, and their, it has no apostrophe.

  • Whose turn is it?
  • She's the designer whose work I love.

Whose can also refer to things: a company whose app I use every day.

The test #

Replace the word with "who is" or "who has."

  • Still makes sense → who's
  • Doesn't → whose

___ bag is this? → "Who is bag is this?" No. So: Whose bag is this?

Common mistakes #

Wrong Right
Who's car is outside? Whose car is outside?
Whose going first? Who's going first?

Let AI check it #

AI Grammar Checker catches whose/who's mix-ups, along with its/it's and your/you're, in one tap.