in vs io, What's the Difference?

Which to use

“in” is a preposition and “io” is an adverb - they look or sound alike but fill different roles in a sentence.

#269
“in” frequency rank: #18,900
“io” frequency rank: 19169
confusion score

Side-by-Side Comparison

Feature	in	io
Definition	em	sempre

Letter map: in vs io

Shared letters muted; letters that set in and io apart highlighted. Shared run: 1.

2 ch

Part-of-speech tell for in / io

Our dataset has no pronunciation recorded for both members, so the reliable separator here is grammatical: in is apreposition and ioanadverb. On the page they differ by a single letter - n in “in” becomes o in “io”. Our composite confusion score for this pair is 19169, derived from the frequency rank of both members and their visual similarity.

in is recorded at frequency rank #269, classified as aprep. io is at rank #18,900, tagged as anadv, pronounced /ˈi.o/, /ˈi.ɔ/.

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 19169, this pair ranks #51,639 of 75,631 scored Portuguese confusable pairs - roughly mid-pack for confusability.

Orthographic DNA of in vs io

Shared letters: i. Private to "in": n. Private to "io": o.

"in" · 2 letters · shape VC · "io" · 2 letters · shape VV

Frequently Asked Questions

Can "in" and "io" be used interchangeably?

No - they are not even the same part of speech. "in" is a preposition and "io" an adverb, so a sentence built for one is usually ungrammatical with the other.

Which is more common, "in" or "io"?

"in" is the more common of the two: it sits at frequency rank #269 in our Portuguese list, against #18,900 for "io". That is a wide gap, so in ordinary text the rarer spelling is the one worth double-checking.

What to do next

Pair "in" vs "io" is on the table, pick a follow-up below.

Full dictionary entry for "in" with definition, IPA, and generated misspellings. Word entry
Full dictionary entry for "io" - compare definitions side by side with the headword page. Word entry
This pair ranks #51,639 of 75,631 scored Portuguese confusable pairs in this corpus vintage. Corpus statistics
"in" and "io" also get mixed up with nearby pairs, the highest-scored neighbour is "ino vs io". Nearby pair

Confusion rank #51,639 of 75,631 scored Portuguese pairs, corpus vintage 2026-09-03, not spelling advice.