AGL vs API, What's the Difference?

Which to use

“AGL” is a phrase and “API” is a noun - they look or sound alike but fill different roles in a sentence.

#46,290
“AGL” frequency rank: #11,501
“API” frequency rank: 57791
confusion score

Side-by-Side Comparison

Feature	AGL	API
Definition	Initialism of above ground level: designating a measured distance from the ground to a higher level, i.e. altitude.	Initialism of active pharmaceutical ingredient.

Letter map: AGL vs API

Shared letters muted; letters that set AGL and API apart highlighted. Shared run: 1.

3 ch

AGL

3 ch

API

Grammar separator: AGL vs API

Our dataset has no pronunciation recorded for both members, so the reliable separator here is grammatical: AGL is aphrase and APIanoun. On the page they share most of their letters but differ in 2 positions. Our composite confusion score for this pair is 57791, derived from the frequency rank of both members and their visual similarity.

AGL is recorded at frequency rank #46,290, classified as aphrase. API is at rank #11,501, tagged as anoun, pronounced /ˌeɪˌpiˈaɪ/.

Glosses for this pair are partially populated in our dataset, but the full side-by-side definitions above should still guide you to the right choice.

With a confusion score of 57791, this pair ranks #116,926 of 530,003 scored English confusable pairs - among the most confusable pairs.

Orthographic DNA of AGL vs API

Shared letters: a. Private to "AGL": gl. Private to "API": ip.

"AGL" · 3 letters · shape VCC · "API" · 3 letters · shape VCV

Frequently Asked Questions

Do "AGL" and "API" mean the same thing in a sentence?

No - they are not even the same part of speech. "AGL" is a phrase and "API" a noun, so a sentence built for one is usually ungrammatical with the other.

Which is more common, "AGL" or "API"?

"API" is the more common of the two: it sits at frequency rank #11,501 in our English list, against #46,290 for "AGL". The two are close in frequency, so neither is a safe default; check the meaning rather than guessing.

Useful next steps

Pair "AGL" vs "API" is on the table, pick a follow-up below.

Full dictionary entry for "AGL" with definition, IPA, and generated misspellings. Word entry
Full dictionary entry for "API" - compare definitions side by side with the headword page. Word entry
This pair ranks #116,926 of 530,003 scored English confusable pairs in this corpus vintage. Corpus statistics
"AGL" and "API" also get mixed up with nearby pairs, the highest-scored neighbour is "AGL vs amb". Nearby pair

Confusion rank #116,926 of 530,003 scored English pairs, corpus vintage 2026-09-03, not spelling advice.