These two terms cause confusion even for native speakers. In fact, using them wrongly may be the Number One Error in English! But they are actually quite easy to use correctly, when you understand the rule. Note that their pronunciation is identical (exactly the same).

its = possessive form of it.
it's = short for it is, it has.

•its

The word its is a possessive adjective for things and animals, similar to his and her

The boy broke his leg.
The girl broke her leg.
The dog broke its leg.
The company pays its workers on Fridays.
My car needs to have its tyres checked.
A chain is as strong as its weakest link.

•it's

The term it's is a contraction, short for "it is" or "it has".

Here are some example sentences:

•it is

It's late.
I wonder why it's so cold.
It's not raining.
They can't come because it's snowing.

•it has

-It's been raining for hours.
-Do you think it's arrived?
-I hope it's got a bathroom.

Really Simple English Grammar. Essentials

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It’s or Its?

Most people know that the short version of it is is spelled it’s. After all, an apostrophe replaces a missing letter, which in this case is the i in is. And we know how to spell he’s and she’s. So we write, “It’s going to rain,” not “Its going to rain,” unless we’re typing too fast and leave out the apostrophe accidentally.

But misspelling the possessive form of it is a little more common. So, when writing about something which belongs to someone or something, which is it: it’s or its?

Well, the answer is its, as in “He put on the raincoat and fastened its snaps.” The possessive form of it has no apostrophe.

You can just memorize that and get used to it, but to help you remember, you could keep in mind that other possessive adjectives, such as his and her, do not have apostrophes either.

Here are some quotations from newspapers

1) Our favorite affordable robot vacuum just got an upgrade—and it’s on sale. … The RoboVac 11 from Eufy is the best affordable robot vacuum we’ve ever tested, and easily the most popular model among our readers. But it may soon be unseated by its upgraded version—the Eufy RobotVac …

2) With the sequel ‘Jumanji: Welcome to the Jungle’ swinging into theaters, we decided to take a look back at its predecessor that had us peering ..

3) Google Pay joins together its Android Pay service with Google Wallet.