ill vs io, What's the Difference?

Which to use

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

#25,175
“ill” frequency rank: #26,465
“io” frequency rank: 51640
confusion score

Side-by-Side Comparison

Feature	ill	io
Definition	schlecht, falsch	Für die 1. Person Singular Nominativ/Subjektfall – im Objektfall: siehe me

Letter map: ill vs io

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

3 ch

ill

2 ch

Role in the sentence - ill and io

Our dataset has no pronunciation recorded for both members, so the reliable separator here is grammatical: ill is anadverb and ioapronoun. On the page they differ by 1 letter(s) in length. Our composite confusion score for this pair is 51640, derived from the frequency rank of both members and their visual similarity.

ill is recorded at frequency rank #25,175, classified as anadv, pronounced [ɪl]. io is at rank #26,465, tagged as apron, pronounced […].

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 51640, this pair ranks #1,127,851 of 2,006,359 scored German confusable pairs - roughly mid-pack for confusability.

Orthographic DNA of ill vs io

Shared letters: i. Private to "ill": l. Private to "io": o.

"ill" · 3 letters · shape VCC · "io" · 2 letters · shape VV

Frequently Asked Questions

Is swapping "ill" for "io" ever safe?

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

Frequency check: "ill" vs "io" - which ranks higher?

"ill" is the more common of the two: it sits at frequency rank #25,175 in our German list, against #26,465 for "io". The two are close in frequency, so neither is a safe default; check the meaning rather than guessing.

Useful next steps

You've compared "ill" and "io". Here's where to go from here.

Full dictionary entry for "ill" 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 #1,127,851 of 2,006,359 scored German confusable pairs in this corpus vintage. Corpus statistics
"ill" and "io" also get mixed up with nearby pairs, the highest-scored neighbour is "io vs puzzles". Nearby pair

Confusion rank #1,127,851 of 2,006,359 scored German pairs, corpus vintage 2026-09-03, not spelling advice.