faivsFsConfusable pair

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

Which to use

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

#11,967
“fai” frequency rank
#28,962
“Fs” frequency rank
40929
confusion score

Side-by-Side Comparison

Feature fai Fs
Definition Deuxième personne du pluriel de l’indicatif présent de fer. Pluriel de F.

Where the eye mixes fai and Fs

Muted = shared; highlighted = the visual trap. They share 1 letter in sequence.

3 ch
fai
2 ch
Fs

Look-alike desk: fai vs Fs

These two trip readers on the page rather than in the ear: fai is [ˈfa.i] while Fs is \ɛfs\. 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 (verb vs noun), which is usually the fastest check. Our composite confusion score for this pair is 40929, derived from the frequency rank of both members and their visual similarity.

fai is recorded at frequency rank #11,967, classified as averb, pronounced [ˈfa.i]. Fs is at rank #28,962, tagged as anoun, pronounced \ɛfs\.

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 40929, this pair ranks #236,883 of 440,172 scored French confusable pairs - roughly mid-pack for confusability.

Orthographic DNA of fai vs Fs

Shared letters: f. Private to "fai": ai. Private to "Fs": s.

"fai" · 3 letters · shape CVV  ·  "Fs" · 2 letters · shape CC

Frequently Asked Questions

Is swapping "fai" for "Fs" ever safe?
No - they are not even the same part of speech. "fai" is a verb and "Fs" a noun, so a sentence built for one is usually ungrammatical with the other.
In ordinary French text, does "fai" or "Fs" show up more?
"fai" is the more common of the two: it sits at frequency rank #11,967 in our French list, against #28,962 for "Fs". 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 "fai" and "Fs" is sorted above. Next: full entries or other pairs that share a letter shape.

  • Full dictionary entry for "fai" with definition, IPA, and generated misspellings. Word entry
  • Full dictionary entry for "Fs" - compare definitions side by side with the headword page. Word entry
  • This pair ranks #236,883 of 440,172 scored French confusable pairs in this corpus vintage. Corpus statistics
  • "fai" and "Fs" also get mixed up with nearby pairs, the highest-scored neighbour is "Fee vs Fs". Nearby pair

Confusion rank #236,883 of 440,172 scored French pairs, corpus vintage 2026-09-03, not spelling advice.

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

Source: FrequencyWords open word-frequency list