Which to use
“foi” is a noun and “foul” is an adjective - they look or sound alike but fill different roles in a sentence.
- #42,644
- “foi” frequency rank
- #6,574
- “foul” frequency rank
- 49218
- confusion score
Side-by-Side Comparison
| Feature | foi | foul |
|---|---|---|
| Definition | A depiction of a handshake. | Covered with, or containing unclean matter; dirty. |
Letter map: foi vs foul
Shared letters muted; letters that set foi and foul apart highlighted. Shared run: 2.
Grammar separator: foi vs foul
Our dataset has no pronunciation recorded for both members, so the reliable separator here is grammatical: foi is anoun and foulanadjective. On the page they differ by 1 letter(s) in length. Our composite confusion score for this pair is 49218, derived from the frequency rank of both members and their visual similarity.
foi is recorded at frequency rank #42,644, classified as anoun. foul is at rank #6,574, tagged as anadj, pronounced /faʊl/.
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 49218, this pair ranks #185,680 of 530,003 scored English confusable pairs - roughly mid-pack for confusability.
Orthographic DNA of foi vs foul
Shared letters: fo. Private to "foi": i. Private to "foul": lu.
"foi" · 3 letters · shape CVV · "foul" · 4 letters · shape CVVC
Known mistypes of this pair
- foul ← ffoul · folu · foull · fuol · oful
Frequently Asked Questions
Can "foi" and "foul" be used interchangeably?
Which is more common, "foi" or "foul"?
After this comparison
Pair "foi" vs "foul" is on the table, pick a follow-up below.
- Full dictionary entry for "foi" with definition, IPA, and generated misspellings. Word entry
- Full dictionary entry for "foul" - compare definitions side by side with the headword page. Word entry
- This pair ranks #185,680 of 530,003 scored English confusable pairs in this corpus vintage. Corpus statistics
- "foi" and "foul" also get mixed up with nearby pairs, the highest-scored neighbour is "foi vs FOMO". 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 #185,680 of 530,003 scored English pairs, corpus vintage 2026-09-03, not spelling advice.