API vs AZ, What's the Difference?

Which to use

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

#11,501
“API” frequency rank: #11,504
“AZ” frequency rank: 23005
confusion score

Side-by-Side Comparison

Feature	API	AZ
Definition	Initialism of active pharmaceutical ingredient.	Abbreviation of Arizona: a state of the United States.

Letter map: API vs AZ

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

3 ch

API

2 ch

Grammar separator: API vs AZ

Our dataset has no pronunciation recorded for both members, so the reliable separator here is grammatical: API is anoun and AZaname. On the page they differ by 1 letter(s) in length. Our composite confusion score for this pair is 23005, derived from the frequency rank of both members and their visual similarity.

API is recorded at frequency rank #11,501, classified as anoun, pronounced /ˌeɪˌpiˈaɪ/. AZ is at rank #11,504, tagged as aname.

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 23005, this pair ranks #412,422 of 530,003 scored English confusable pairs - a relatively easy-to-tell-apart pair.

Orthographic DNA of API vs AZ

Shared letters: a. Private to "API": ip. Private to "AZ": z.

"API" · 3 letters · shape VCV · "AZ" · 2 letters · shape VC

Frequently Asked Questions

Can "API" and "AZ" be used interchangeably?

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

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

"API" is the more common of the two: it sits at frequency rank #11,501 in our English list, against #11,504 for "AZ". The two are close in frequency, so neither is a safe default; check the meaning rather than guessing.

Useful next steps

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

Full dictionary entry for "API" with definition, IPA, and generated misspellings. Word entry
Full dictionary entry for "AZ" - compare definitions side by side with the headword page. Word entry
This pair ranks #412,422 of 530,003 scored English confusable pairs in this corpus vintage. Corpus statistics
"API" and "AZ" also get mixed up with nearby pairs, the highest-scored neighbour is "amb vs AZ". Nearby pair

Confusion rank #412,422 of 530,003 scored English pairs, corpus vintage 2026-09-03, not spelling advice.