duffvsdutyWhich spelling fits?

Which to use

“duff” and “duty” are a confusable French pair: similar on the page, but distinct in meaning, check the gloss before you choose.

#34,065
“duff” frequency rank
#20,990
“duty” frequency rank
55055
confusion score

Side-by-Side Comparison

Feature duff duty
Definition Pâte à gâteau. Devoir.

Where the eye mixes duff and duty

Muted = shared; highlighted = the visual trap. They share 2 letters in sequence.

4 ch
duff
4 ch
duty

Visual trap between duff and duty

A purely visual mix-up. duff (\dʌf\) and duty (\ˈdju.ti\) are said differently, so reading them aloud is the quickest way to catch the wrong one. On the page they stay close: they share most of their letters but differ in 2 positions. Our composite confusion score for this pair is 55055, derived from the frequency rank of both members and their visual similarity.

duff is recorded at frequency rank #34,065, classified as anoun, pronounced \dʌf\. duty is at rank #20,990, tagged as anoun, pronounced \ˈdju.ti\.

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 55055, this pair ranks #129,949 of 440,172 scored French confusable pairs - roughly mid-pack for confusability.

Orthographic DNA of duff vs duty

Shared letters: du. Private to "duff": f. Private to "duty": ty.

"duff" · 4 letters · shape CVCC  ·  "duty" · 4 letters · shape CVCV

Known mistypes of this pair

  • duffdduff · dfuf · duf · udff
  • dutydduty · dtuy · dutty · dutyy · duyt · udty

Frequently Asked Questions

Can "duff" and "duty" be used interchangeably?
No. They are said differently (\dʌf\ versus \ˈdju.ti\) and carry different meanings; reading the sentence aloud is usually enough to catch the wrong one.
Frequency check: "duff" vs "duty" - which ranks higher?
"duty" is the more common of the two: it sits at frequency rank #20,990 in our French list, against #34,065 for "duff". The two are close in frequency, so neither is a safe default; check the meaning rather than guessing.

Useful next steps

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

  • Full dictionary entry for "duff" with definition, IPA, and generated misspellings. Word entry
  • Full dictionary entry for "duty" - compare definitions side by side with the headword page. Word entry
  • This pair ranks #129,949 of 440,172 scored French confusable pairs in this corpus vintage. Corpus statistics
  • "duff" and "duty" also get mixed up with nearby pairs, the highest-scored neighbour is "duff vs dust". 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 #129,949 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