Ago vs Before

When to use each in English, with meaning, register, and examples.

Ago

Top 1,000 (very common) A1 adverb

Before

Top 1,000 (very common) A1 preposition

	Ago	Before
Pronunciation	🇬🇧 /["/əˈɡəʊ/"]/ 🇺🇸 /["/əˈɡəʊ/"]/	🇬🇧 /["/bɪˈfɔː(r)/"]/ 🇺🇸 /["/bɪˈfɔːr/"]/
Meaning	in the past; before now	At an earlier time than something else.
Example	two weeks/months/years ago	I always wash my hands before dinner.
Register	Neutral	Neutral
How common	Top 1,000 (very common)	Top 1,000 (very common)
CEFR level	A1	A1
Part of speech	adverb	preposition
Collocations	two years ago, just ago, long ago	before dinner, before school, before sunrise
Antonyms	future	after, following
Common mistakes	Incorrectly using 'ago' with future events., Confusing 'ago' with 'since' when discussing past time., Omitting the time expression, e.g., saying 'I saw him ago.'	Confusing 'before' with 'after'., Using 'before' to refer to an event that can only happen afterwards., Omitting the necessary clause or event after 'before'.
Usage notes	Use 'ago' to refer to a specific time in the past. It's typically used in informal and neutral contexts, but avoid using it in very formal writing or speeches.	Used to indicate a time prior to an event or action. Common in both spoken and written language. Avoid using it in extremely formal writing; in that context, consider 'prior to'.

See it in real clips

We sent people into it. Ten years ago.

The Pitt › S1 E1

on the SBO three hours ago.

The Lord Of The Rings › The return of the king

Not two days ago.

We sent people into it. Ten years ago.

The Pitt › S1 E1

on the SBO three hours ago.

Ago

Frequently asked questions: Ago vs Before

What's the difference between Ago and Before?

Ago: in the past; before now Before: At an earlier time than something else.

Are Ago and Before the same CEFR level?

Ago: A1, Before: A1 on the CEFR scale.

What part of speech are Ago and Before?

Ago: adverb, Before: preposition.

Can you show an example of each?

Ago: two weeks/months/years ago Before: I always wash my hands before dinner.

Can I use Ago and Before interchangeably?

Not always. Ago and Before are related and overlap in some contexts, but they differ in register, how common they are, and usage, so swapping one for another can change the meaning or tone. Check the differences above before substituting.