The key to using its and it’s correctly is to not think about it too much.
Plural, contraction, and possessive ‘s’
We learn very early in our language education that putting an ‘s’ on the end of a noun word makes it plural. “Zebra” refers to one single stripe-ey horse, while “zebras” refers to at least two stripe-ey horses.
We also learn that a word with an apostrophe and an ‘s’ on the end makes that word possessive—“a zebra’s stripes,” or “Kevin’s book bag.” The apostrophe ‘s’ construction shows that word’s ownership over whatever comes next.
Then there’s the matter of contractions. The apostrophe ‘s’ construction, in those cases, represents the word “is” or “has.”
Mom’s gone to the grocery store.
Mary’s running a mile each morning until the day of the race.
So it’s very easy to mistakenly use “it’s” in a possessive role. But doing so is incorrect.
Here’s the rule.
“It’s” can only mean “it is” or “it has.” It is always a contraction if it has an apostrophe. Always.
“Its” is always used in a possessive role. Always.
Unlike many grammatical rules, there are NO exceptions to this rule.
You may be pulling your hair out trying to figure out why this is the case, and the answer will probably let you down. That confusion you’re feeling right now? You are far from the first person to have trouble with these words.
In fact, until a few hundred years ago, “it’s” could function as the possessive of “it.” Readers used context to know what the writer meant, which wasn’t hard. However, the ambiguity caused a lot of turmoil when it came to the actual writing. In the professional world, even an error as small as this can completely undermine your sense of professionalism.
To solve the problem, folks nixed the apostrophe in the possessive form to mirror other possessive pronouns like “his,” “hers,” and “theirs.”
It’s: a contraction for “it has” or “it is.”
If you have trouble deciding, read the sentence to yourself, and in place of “it’s” or “its,” say “it is” or “it has.” If the sentence no longer makes sense, then it gets no apostrophe.
Try a few of these for practice.
(Its, It’s) almost certain that our store’s new sign will bring in new customers.
Even if (its, it’s) raining, they are still going to play the soccer match.
Karen always laughs when her dog chases (its, it’s) tail.
(Its, It’s) perfectly fine with me if you use my chef’s knife, as long as you put it back in (its, it’s) case when you’re done.
I told my daughter that (its, it’s) fine if she made a B on her test, if (its, it’s) the best she can do.
The herd of zebra made (its, it’s) way across the plain.
Because (its, it’s) the anniversary of Martin Luther King’s death, we read a speech of his in class.
Before going on the trip, check your oil. I think (its, it’s) about time to change it.
We found out our pet chinchilla was a girl, so we changed (its, it’s) name.
After reading that book on advertising, (its, it’s) incredible to see how much the industry has changed (its, it’s) methods and how far (its, it’s) come.
Answers: 1. It’s, 2. it’s, 3. its, 4. It’s, its, 5. it’s, it’s, 6. its, 7. it’s, 8. it’s, 9. its, 10. it’s, its, it’s