aovsarWhich spelling fits?

Quick tell: ao is a contraction, ar is a noun, so they fill different roles in a sentence.

Which to use

“ao” is a contraction and “ar” is a noun - they look or sound alike but fill different roles in a sentence.

#27
“ao” frequency rank
#613
“ar” frequency rank
640
confusion score

Side-by-Side Comparison

Feature ao ar
Definition contração da preposição a com o artigo definido o fluido gasoso que envolve todo o planeta Terra; atmosfera

Letter map: ao vs ar

Shared letters muted; letters that set ao and ar apart highlighted. Shared run: 1.

2 ch
ao
2 ch
ar

Role in the sentence - ao and ar

Our dataset has no pronunciation recorded for both members, so the reliable separator here is grammatical: ao is acontraction and aranoun. On the page they differ by a single letter - o in “ao” becomes r in “ar”. Our composite confusion score for this pair is 640, derived from the frequency rank of both members and their visual similarity.

ao is recorded at frequency rank #27, classified as acontraction, pronounced /aw/. ar is at rank #613, tagged as anoun.

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 640, this pair ranks #75,029 of 75,631 scored Portuguese confusable pairs - a relatively easy-to-tell-apart pair.

Orthographic DNA of ao vs ar

Shared letters: a. Private to "ao": o. Private to "ar": r.

"ao" · 2 letters · shape VV  ·  "ar" · 2 letters · shape VC

Frequently Asked Questions

Is swapping "ao" for "ar" ever safe?
No - they are not even the same part of speech. "ao" is a contraction and "ar" a noun, so a sentence built for one is usually ungrammatical with the other.
Which is more common, "ao" or "ar"?
"ao" is the more common of the two: it sits at frequency rank #27 in our Portuguese list, against #613 for "ar". That is a wide gap, so in ordinary text the rarer spelling is the one worth double-checking.

After this comparison

Done with this confusable. These links stay specific to "ao" and "ar".

  • Full dictionary entry for "ao" with definition, IPA, and generated misspellings. Word entry
  • Full dictionary entry for "ar" - compare definitions side by side with the headword page. Word entry
  • This pair ranks #75,029 of 75,631 scored Portuguese confusable pairs in this corpus vintage. Corpus statistics
  • "ao" and "ar" also get mixed up with nearby pairs, the highest-scored neighbour is "acs vs ar". Nearby pair

Confusion rank #75,029 of 75,631 scored Portuguese pairs, corpus vintage 2026-09-03, not spelling advice.

Source: Wiktionary (via kaikki.org) Structured Wiktionary extract

Source: FrequencyWords open word-frequency list