Bad vs. Badly – What’s the Difference?

When learning English, it can be difficult to tell the difference between adjectives and adverbs. Many languages use the same word as both an adjective and an adverb; a French person, for instance, might use mal to describe a bad baguette and to say that the baguettes have been burned badly.

In English though, bad and badly are different parts of speech, and careful writing requires their correct use. Continue reading to find out how to choose between these words.

What is the Difference Between Bad and Badly?

In this article, I will compare bad vs badly. I will provide several example sentences to demonstrate how these words look in context.

Then, at the end, I will show you a mnemonic device that makes choosing bad or badly much easier.

When to Use Bad

bad versus badlyWhat does bad mean? Bad is an adjective. Describing something that is not up to acceptable quality standards, bad is the opposite of good.

Adjectives modify nouns by describing their qualities. Bad is a versatile word—children can have bad behavior, a sandwich can have a bad aftertaste, and an athlete can have a bad game. The word is applicable to almost any context.

Here are a few sentence examples,

  • “One bad apple can spoil the whole bushel,” warned Old Nance.
  • Because our product got almost universally bad reviews at online retailers, we manufactured it in a different color plastic and hired an outside marketing firm to help with rebranding.
  • Ten good deeds cannot make up for one bad decision once one’s reputation has been damaged.
  • The auto-finance sector has taken a bad turn. An investor update on Tuesday from auto lender Ally Financial, formerly the auto-lending arm of General Motors, added to building evidence that trend lines are negative in the industry. –The Wall Street Journal

Of course, since bad is so versatile, it is also incredibly vague. You should usually try to think of a more specific adjective to use instead.

When to Use Badly

Definition of badly definition of bad definitionWhat does badly mean? Badly is an adverb. It describes an action that has been carried out poorly.

Adverbs modify verbs by describing how they have been performed.

For example,

  • I scored badly on my ethics exam, and I am now prohibited from practicing law in the state of Kentucky.
  • When a pitcher pitches badly, his offense has a lot of work to do to keep the team in the game.
  • The onions are badly burned, which gives the entire dish an acrid flavor reminiscent of a grease fire.
  • North Carolina got 22 points from Joel Berry II, but as a team shot badly: just 36 percent, with Jackson going 6 for 19 and 0 for 9 from 3 points. –The New York Times

Trick to Remember the Difference

Define badly and define badNow, let’s go over a trick to remember badly vs. bad.

Choosing one of these words over the other is very easy since they are different parts of speech.

  • If you are using the word as an adjective, simply use bad.
  • If you are using the word as an adverb, add the -ly prefix to form the adverb badly.

The telltale -ly is the signal that badly is an adverb. It shares that suffix with many other adverbs, like its synonyms poorly, imperfectly, and shabbily. You can use this suffix as a reminder that badly should always be used as an adverb.


Is it bad or badly? Bad and badly are two words that describe things that are not up to snuff.

  • Bad is an adjective, which means it describes nouns.
  • Badly, as an adverb, modifies verbs.

You can use the suffix -ly as a reminder that badly is an adverb, since many other adverbs also end in -ly.

Any time you have a question about confusing words or other writing topics, be sure to check back with Writing Explained. And, if you ever get stuck choosing badly or bad in the future, come back and reference this article.