iffvsinfoWhich spelling fits?

Quick tell: iff is a conjunction, info is a noun, so they fill different roles in a sentence.

Which to use

“iff” is a conjunction and “info” is a noun - they look or sound alike but fill different roles in a sentence.

#45,443
“iff” frequency rank
#2,489
“info” frequency rank
47932
confusion score

Side-by-Side Comparison

Feature iff info
Definition Abbreviation of if and only if. information.

Where the eye mixes iff and info

Muted = shared; highlighted = the visual trap. They share 2 letters in sequence. iff runs 3 letters (VCC) against info's 4 (VCCV) - the length gap alone is often enough to separate them once you know to check it.

3 ch
iff
4 ch
info

Why the eye confuses iff with info

These two trip readers on the page rather than in the ear: iff is /ɪf ən(d)ˈəʊn.li ɪf/ while info is /ˈɪnfəʊ/. Spoken aloud the problem disappears. In writing it persists, because they differ by 1 letter(s) in length, and the parts of speech differ too (conjunction vs noun), which is usually the fastest check. Our composite confusion score for this pair is 47932, derived from the frequency rank of both members and their visual similarity.

iff is recorded at frequency rank #45,443, classified as aconj, pronounced /ɪf ən(d)ˈəʊn.li ɪf/. info is at rank #2,489, tagged as anoun, pronounced /ˈɪnfəʊ/.

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 47932, this pair ranks #197,835 of 530,003 scored English confusable pairs - roughly mid-pack for confusability.

Orthographic DNA of iff vs info

Shared letters: fi. Private to "iff": -. Private to "info": no.

"iff" · 3 letters · shape VCC  ·  "info" · 4 letters · shape VCCV

Known mistypes of this pair

  • info ← ifno · inffo · innfo · inof · nifo

Frequently Asked Questions

Is swapping "iff" for "info" ever safe?
No - they are not even the same part of speech. "iff" is a conjunction and "info" a noun, so a sentence built for one is usually ungrammatical with the other.
In ordinary English text, does "iff" or "info" show up more?
"info" is the more common of the two: it sits at frequency rank #2,489 in our English list, against #45,443 for "iff". That is a wide gap, so in ordinary text the rarer spelling is the one worth double-checking.

After this comparison

Eye-level mix-up between "iff" and "info" is sorted above. Next: full entries or other pairs that share a letter shape.

  • Full dictionary entry for "iff" with definition, IPA, and generated misspellings. Word entry
  • Full dictionary entry for "info" - compare definitions side by side with the headword page. Word entry
  • This pair ranks #197,835 of 530,003 scored English confusable pairs in this corpus vintage. Corpus statistics
  • "iff" and "info" also get mixed up with nearby pairs, the highest-scored neighbour is "iff vs ith". Nearby pair
  • Recorded mistypes exist for at least one side of this pair, useful when a spell-checker or OCR lands on the wrong form. See mistypes

Confusion rank #197,835 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