IBvsioTell them apart

Which to use

“IB” and “io” are a confusable English pair: similar on the page, but distinct in meaning, check the gloss before you choose.

#16,046
“IB” frequency rank
#16,946
“io” frequency rank
32992
confusion score

Side-by-Side Comparison

Feature IB io
Definition An International Baccalaureate program A type of moth, the io moth.

Letter map: IB vs io

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

2 ch
IB
2 ch
io

Spelling & dictionary notes on IB vs io

IB and io are indexed as a confusable English pair. We have no recorded pronunciation or part of speech for both members, so the spelling overlap is what we can show you: they differ by a single letter - b in “IB” becomes o in “io”. Our composite confusion score for this pair is 32992, derived from the frequency rank of both members and their visual similarity.

IB is recorded at frequency rank #16,046, classified as anoun. io is at rank #16,946, tagged as anoun, pronounced /ˈaɪəʊ/.

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 32992, this pair ranks #333,167 of 530,003 scored English confusable pairs - roughly mid-pack for confusability.

Orthographic DNA of IB vs io

Shared letters: i. Private to "IB": b. Private to "io": o.

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

Frequently Asked Questions

Is swapping "IB" for "io" ever safe?
No. They differ by a single letter - b in “IB” becomes o in “io”, but the dictionary glosses above give them different meanings, so swapping one for the other changes what the sentence says.
Frequency check: "IB" vs "io" - which ranks higher?
"IB" is the more common of the two: it sits at frequency rank #16,046 in our English list, against #16,946 for "io". The two are close in frequency, so neither is a safe default; check the meaning rather than guessing.

What to do next

Done with this confusable. These links stay specific to "IB" and "io".

  • Full dictionary entry for "IB" 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 #333,167 of 530,003 scored English confusable pairs in this corpus vintage. Corpus statistics
  • "IB" and "io" also get mixed up with nearby pairs, the highest-scored neighbour is "io vs ith". Nearby pair

Confusion rank #333,167 of 530,003 scored English pairs, corpus vintage 2026-09-03, not spelling advice.

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

Source: FrequencyWords open word-frequency list