Is it "affect" or "effect"?

Use "affect" when you need a verb meaning "to influence" (the weather affected our plans). Use "effect" when you need a noun meaning "a result" (the weather had an effect on our plans). If you can swap in "influence" as a verb, it's affect. If you can swap in "result", it's effect.

Can "effect" be a verb?

Yes, but it's rare and formal. To "effect" something means to bring it about: "The new manager effected sweeping changes." It doesn't mean "influence". If you mean "influence", use affect.

Can "affect" be a noun?

Yes, but only in psychology, where "affect" (pronounced AF-ekt) means a person's visible emotional expression: "The patient showed a flat affect." In everyday English you will almost never need this meaning.

What's the difference between "affected" and "effected"?

"Affected" is the past tense of affect: "The storm affected thousands of homes." "Effected" is the past tense of the rare verb "effect": "The company effected a complete restructuring." In most writing, "affected" is the one you want.

Is "the affect of" ever correct?

Almost never. "The effect of" is the correct phrase in nearly every case: "the effect of caffeine on sleep". Because "effect" is the noun, it's the word that follows "the" or "an".

What's an easy way to remember affect vs effect?

Use RAVEN: Remember, Affect is a Verb, Effect is a Noun. Another quick check is substitution: try replacing the word with "influence" (verb, affect) or "result" (noun, effect) and see which one makes sense.

Affect vs Effect: The Simple Trick to Never Mix Them Up

You write: "The new schedule will affect / effect everyone." You pause. You type one, delete it, type the other, and then open a new tab to look it up. If that sounds familiar, you are in good company, because affect and effect are among the most confused words in English. The good news is that one simple rule covers about 95% of cases, and this guide gives you that rule, a memory trick that actually sticks, the rare exceptions most guides skip, and a short quiz to prove you've got it.

The short answer: affect is usually a verb meaning "to influence", and effect is usually a noun meaning "a result".

Affect vs effect at a glance
The RAVEN trick
How to use "affect"
How to use "effect"
The exceptions most guides skip
Affect vs effect in real situations
5 common mistakes
Test yourself

Affect vs effect at a glance

	Affect	Effect
Usually a...	verb	noun
Meaning	to influence or change	a result or outcome
Example	Lack of sleep affects* your memory.*	Lack of sleep has a bad effect* on your memory.*
Quick test	Can you swap in "influence"?	Can you swap in "result"?

And the two rare uses, which you will meet far less often:

	Word	Meaning	Example
Rare verb	effect	to bring about	The union effected* a change in the law.*
Rare noun	affect	a visible emotional state (psychology)	The patient had a flat affect.

The RAVEN trick: how to remember the difference

Here is the memory hook that makes this stick:

Remember: Affect is a Verb, Effect is a Noun. → RAVEN

Both words follow the order of the alphabet, too: Affect comes before Effect, just as an action (verb) happens before its end result (noun). If you do something, that action affects things, and what comes out the other side is the effect.

The substitution test is a second safety net. Replace the word with one of these and see what still works:

If "influence" fits as a verb, write affect.
If "result" fits as a noun, write effect.

The rain ___ our plans. → "The rain influenced our plans" works, so it's affected. The rain had an ___ on our plans. → after "an" you need a noun, and "result" fits that slot, so it's effect.

Test yourself with a free grammar quiz →

How to use "affect"

Affect as a verb: to influence

Affect is something that happens to a person or thing. It always needs an object, meaning the thing being influenced.

The weather affects my mood.
Smoking affects your lungs.
The strike will affect thousands of commuters.
How does social media affect teenagers?
The new law didn't affect small businesses.

Affect with feelings and health

Affect is especially common when we talk about emotion or health:

The news affected her deeply. (She was emotionally moved.)
The disease affects the nervous system.

"Affected" as an adjective

Affected can also describe a person who is trying too hard to seem impressive, or something that has been influenced:

He spoke in an affected accent that didn't sound natural. (artificial)
Affected areas were evacuated. (influenced by something)

How to use "effect"

Effect as a noun: a result

Effect names the result. You will usually see it after the, an, any, no, little, great, positive or negative.

The effect of the medicine was immediate.
Music has a calming effect on children.
The new policy had no effect on prices.
What is the effect of caffeine on sleep?
The film's effects were stunning.

Phrases with "effect"

Many fixed expressions use effect, so these are worth learning as chunks:

Phrase	Meaning	Example
take effect	begin to work or apply	The new rules take effect on Monday.
side effect	an extra, often unwanted result	Drowsiness is a common side effect.
in effect	in practice, essentially	The rule is, in effect, a ban.
special effects	movie or video tricks	The special effects were incredible.
cause and effect	the link between an action and its result	There's a clear cause and effect here.
to that effect	with that general meaning	He said he was leaving, or words to that effect.

Effect vs impact vs result

Effect, impact and result often overlap. Result is the most neutral, effect stresses the change something caused, and impact usually suggests a stronger or bigger effect. In a test, if you are unsure, "effect" is the safe noun.

The exceptions most guides skip

The simple rule (affect = verb, effect = noun) is right about 95% of the time. These are the other 5%, and knowing them explains why "effect can only be a noun" isn't quite true.

Effect as a verb: to bring about

As a verb, effect means "to make something happen", and it usually goes with words like change, reform, a transformation or a cure. It is formal and fairly rare.

The protesters wanted to effect change in government.
The new CEO effected a complete restructuring of the company.

The difference is subtle: to affect change would mean to influence it, while to effect change means to actually cause it. If you are not sure you need this meaning, you probably want affect.

Affect as a noun: emotional expression

In psychology, affect (stressed on the first syllable: AF-ekt) is a noun for the emotion a person displays.

The patient showed a flat affect during the interview.
Therapists study how affect changes over time.

You will see this in textbooks and clinical writing. In ordinary conversation, you can ignore it.

Affect vs effect in real situations

At work (email): The delay will affect our delivery date. ✓ The delay will have a serious effect on our delivery date. ✓

In school or academic writing: Researchers studied how sleep affects memory. ✓ The study found a significant effect of sleep on memory. ✓

In health and medicine: This medication may affect your balance. ✓ Dizziness is a possible side effect. ✓

In everyday speech: Coffee doesn't affect me at all. ✓ Coffee has no effect on me. ✓

Notice the pattern: the verb sentences use affect, and the noun sentences (with a, no, the, or significant) use effect. Both versions of each pair say the same thing.

5 common mistakes (and how to fix them)

~~The weather effected our plans.~~ → The weather affected our plans. (You need a verb meaning "influenced".)
~~The medicine had a positive affect.~~ → The medicine had a positive effect. (After "a positive", you need a noun.)
~~What is the affect of social media on teens?~~ → What is the effect of social media on teens? ("The ... of" takes a noun.)
~~Noise can negatively effect sleep.~~ → Noise can negatively affect sleep. ("Negatively" modifies a verb here.)
~~The new rule will have an affect on everyone.~~ → The new rule will have an effect on everyone. ("have an ___" takes a noun.)

A pattern to remember: have an effect on, affect with no preposition. You affect something directly (no "on"), but you have an effect on it.

Test yourself: 6 quick questions

Fill in each blank with affect or effect (in the right form). Answers are right below.

Lack of exercise can ______ your health.
The medicine had no ______ on his headache.
How will the new tax ______ small businesses?
The new law takes ______ next month.
Loud music can have a negative ______ on concentration.
Her sad story really ______ me.

Answers:

affect (verb: influence)
effect (noun: result, after "no")
affect (verb: influence)
effect (noun: part of the phrase "take effect")
effect (noun: after "a negative")
affected (verb, past tense: emotionally moved)

Scored 5 or 6? You have this. Scored 3 or 4? Re-read the RAVEN trick and try again. Either way, the best way to lock it in is to practice with real quiz questions.

Practice grammar quizzes →

Quick recap

Affect = usually a verb, meaning to influence.
Effect = usually a noun, meaning a result.
Remember RAVEN: Affect is a Verb, Effect is a Noun.
Rare exceptions: effect as a verb means "to bring about", and affect as a noun is a psychology term.

Keep learning

Another pair of lookalike words: Its vs It's: How to Never Confuse Them Again
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