failvsfoiWhat's the difference?

Quick tell: fail is a verb, foi is a noun, so they fill different roles in a sentence.

Which to use

“fail” is a verb and “foi” is a noun - they look or sound alike but fill different roles in a sentence.

#2,441
“fail” frequency rank
#42,644
“foi” frequency rank
45085
confusion score

Side-by-Side Comparison

Feature fail foi
Definition To be unsuccessful. A depiction of a handshake.

Letter map: fail vs foi

Shared letters muted; letters that set fail and foi apart highlighted. Shared run: 2. fail runs 4 letters (CVVC) against foi's 3 (CVV) - the length gap alone is often enough to separate them once you know to check it.

4 ch
fail
3 ch
foi

Part-of-speech tell for fail / foi

Our dataset has no pronunciation recorded for both members, so the reliable separator here is grammatical: fail is averb and foianoun. On the page they differ by 1 letter(s) in length. Our composite confusion score for this pair is 45085, derived from the frequency rank of both members and their visual similarity.

fail is recorded at frequency rank #2,441, classified as averb, pronounced /feɪl/. foi is at rank #42,644, tagged as anoun.

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 45085, this pair ranks #224,563 of 530,003 scored English confusable pairs - roughly mid-pack for confusability.

Orthographic DNA of fail vs foi

Shared letters: fi. Private to "fail": al. Private to "foi": o.

"fail" · 4 letters · shape CVVC  ·  "foi" · 3 letters · shape CVV

Known mistypes of this pair

  • fail ← afil · faill · fali · ffail · fial

Frequently Asked Questions

Is swapping "fail" for "foi" ever safe?
No - they are not even the same part of speech. "fail" is a verb and "foi" a noun, so a sentence built for one is usually ungrammatical with the other.
Frequency check: "fail" vs "foi" - which ranks higher?
"fail" is the more common of the two: it sits at frequency rank #2,441 in our English list, against #42,644 for "foi". That is a wide gap, so in ordinary text the rarer spelling is the one worth double-checking.

After this comparison

Pair "fail" vs "foi" is on the table, pick a follow-up below.

  • Full dictionary entry for "fail" with definition, IPA, and generated misspellings. Word entry
  • Full dictionary entry for "foi" - compare definitions side by side with the headword page. Word entry
  • This pair ranks #224,563 of 530,003 scored English confusable pairs in this corpus vintage. Corpus statistics
  • "fail" and "foi" 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 #224,563 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