The word it’s is a contraction. It’s is a short version of it is. The apostrophe replaces the letter i in is. Always use the contraction it’s when the word could be replaced by the words it is.
The word its is a possessive pronoun. Use the word its when you want to show ownership.
The dog wagged its tail.
The box landed on its side.
The possessive pronoun its does not use an apostrophe.
Anytime you write the word it’s with the apostrophe, you are really saying it is. Only use it’s when the word can be replaced in the sentence with the words it is.
It’s your turn. Decide which of these sentences can use the word it’s. The cat licked ___ paw. Mom says ___ time for dinner. Did you figure it out? Good for you!