Which to use
“impact” is a noun and “impair” is an adjective - they look or sound alike but fill different roles in a sentence.
- #1,818
- “impact” frequency rank
- #25,687
- “impair” frequency rank
- 27505
- confusion score
Side-by-Side Comparison
| Feature | impact | impair |
|---|---|---|
| Definition | Choc d’un projectile contre un corps. | Qui n’est pas pair, qui n’est pas divisible par deux, en parlant d’un nombre entier. |
Where the eye mixes impact and impair
Muted = shared; highlighted = the visual trap. They share 4 letters in sequence. impact (VCCVCC) and impair (VCCVVC) run the same length but a different consonant-vowel pattern - the shape difference is usually the fastest tell.
Visual trap between impact and impair
These two trip readers on the page rather than in the ear: impact is \ɛ̃.pakt\ while impair is \ɛ̃.pɛʁ\. Spoken aloud the problem disappears. In writing it persists, because they share most of their letters but differ in 2 positions, and the parts of speech differ too (noun vs adjective), which is usually the fastest check. Our composite confusion score for this pair is 27505, derived from the frequency rank of both members and their visual similarity.
impact is recorded at frequency rank #1,818, classified as anoun, pronounced \ɛ̃.pakt\. impair is at rank #25,687, tagged as anadj, pronounced \ɛ̃.pɛʁ\.
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 27505, this pair ranks #328,545 of 440,172 scored French confusable pairs - roughly mid-pack for confusability.
Orthographic DNA of impact vs impair
Shared letters: aimp. Private to "impact": ct. Private to "impair": r.
"impact" · 6 letters · shape VCCVCC · "impair" · 6 letters · shape VCCVVC
Known mistypes of this pair
Frequently Asked Questions
Do "impact" and "impair" mean the same thing in a sentence?
Which is more common, "impact" or "impair"?
After this comparison
Visual near-miss handled. Browse the word pages or a neighbour when the next look-alike shows up.
- Full dictionary entry for "impact" with definition, IPA, and generated misspellings. Word entry
- Full dictionary entry for "impair" - compare definitions side by side with the headword page. Word entry
- This pair ranks #328,545 of 440,172 scored French confusable pairs in this corpus vintage. Corpus statistics
- "impact" and "impair" also get mixed up with nearby pairs, the highest-scored neighbour is "impair vs impairs". 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 #328,545 of 440,172 scored French pairs, corpus vintage 2026-09-03, not spelling advice.