failsvsfoilsWhich spelling fits?

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

Which to use

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

#4,600
“fails” frequency rank
#36,565
“foils” frequency rank
41165
confusion score

Side-by-Side Comparison

Feature fails foils
Definition third-person singular simple present indicative of fail plural of foil

Where the eye mixes fails and foils

Muted = shared; highlighted = the visual trap. They share 4 letters in sequence. fails and foils follow the identical consonant-vowel pattern (CVVCC). Same shape at a glance is often the real trap, independent of shared letters.

5 ch
fails
5 ch
foils

Look-alike desk: fails vs foils

These two trip readers on the page rather than in the ear: fails is /feɪlz/ while foils is /fɔɪlz/. Spoken aloud the problem disappears. In writing it persists, because they differ by a single letter - a in “fails” becomes o in “foils”, and the parts of speech differ too (verb vs noun), which is usually the fastest check. Our composite confusion score for this pair is 41165, derived from the frequency rank of both members and their visual similarity.

fails is recorded at frequency rank #4,600, classified as averb, pronounced /feɪlz/. foils is at rank #36,565, tagged as anoun, pronounced /fɔɪlz/.

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 41165, this pair ranks #260,938 of 530,003 scored English confusable pairs - roughly mid-pack for confusability.

Orthographic DNA of fails vs foils

Shared letters: fils. Private to "fails": a. Private to "foils": o.

"fails" · 5 letters · shape CVVCC  ·  "foils" · 5 letters · shape CVVCC

Known mistypes of this pair

  • failsafils · faills · failss · faisl · falis · ffails · fials
  • foilsffoils · fiols · foills · foilss · foisl · folis · ofils

Frequently Asked Questions

Is swapping "fails" for "foils" ever safe?
No - they are not even the same part of speech. "fails" is a verb and "foils" a noun, so a sentence built for one is usually ungrammatical with the other.
Frequency check: "fails" vs "foils" - which ranks higher?
"fails" is the more common of the two: it sits at frequency rank #4,600 in our English list, against #36,565 for "foils". The two are close in frequency, so neither is a safe default; check the meaning rather than guessing.

After this comparison

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

  • Full dictionary entry for "fails" with definition, IPA, and generated misspellings. Word entry
  • Full dictionary entry for "foils" - compare definitions side by side with the headword page. Word entry
  • This pair ranks #260,938 of 530,003 scored English confusable pairs in this corpus vintage. Corpus statistics
  • "fails" and "foils" also get mixed up with nearby pairs, the highest-scored neighbour is "foils vs Foyle". 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 #260,938 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