Commonly Confused

'Affect' vs. 'Effect'

How to pick the right one

What to Know

Affect is usually a verb meaning "to produce an effect upon," as in "the weather affected his mood." Effect is usually a noun meaning "a change that results when something is done or happens," as in "computers have had a huge effect on our lives." There are exceptions, but if you think of affect as a verb and effect as a noun, you’ll be right most of the time.

Affect and effect are two of the most commonly confused words in English, but don’t worry—we’ll help you keep them straight.

The basic difference is this: affect is usually a verb, and effect is usually a noun.

‘Affect’ as a Verb

Affect, when used as a verb, means "to act on or change someone or something."

the drought affected plant growth

construction will affect traffic in the area

trying not to let emotions affect their decision

Affect also has a sense meaning “to put on a false appearance of (something).”

he affected a French accent

’Effect’ as a Noun

As a noun, an effect is "a change that results when something is done or happens," or "a particular feeling or mood created by something."

the second cup of coffee had no effect

he added a scarf to the outfit for effect

the law goes into effect next week

A Few Rare Exceptions

There are, however, a few relatively uncommon exceptions, and these are worth knowing about.

Effect can be a verb. As a verb, effect generally means "to cause to come into being" or "accomplish."

the strike effected change within the company

Affect can be a noun. Although its use is primarily found in psychology, the noun affect refers to an observable emotional response.

his affect did not change after hearing the news

But exceptions aside, just stick to the basics: if you think of affect as the verb and effect as the noun, most of the time you’ll be using the word you want.

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