Is "its" or "it's" the possessive?

Its (no apostrophe) is the possessive. It's (with apostrophe) is short for "it is."

When do I use "it's" with an apostrophe?

Only when you mean "it is" or "it has." Everywhere else, the possessive its has no apostrophe.

Quick answer Canonicalizes to Its vs. It’s

Is it "its a dog" or "it's a dog"?

i · AnswerOne line, no lecture

"It's a dog." The phrase is a contraction of "it is" — the apostrophe belongs.

ii · A little moreWhy this is the one to keep

Say it out loud: it is a dog — that reads naturally, so the contracted form it's is the right one. Its a dog has no apostrophe and reads as though "its" is possessing something that never arrives.

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