Which to use
“auto” and “aux” are a confusable English pair: similar on the page, but distinct in meaning, check the gloss before you choose.
- #3,099
- “auto” frequency rank
- #16,176
- “aux” frequency rank
- 19275
- confusion score
Side-by-Side Comparison
| Feature | auto | aux |
|---|---|---|
| Definition | Clipping of automatic (of a gearbox/transmission). | Abbreviation of auxiliary. |
Where the eye mixes auto and aux
Muted = shared; highlighted = the visual trap. They share 2 letters in sequence.
Visual trap between auto and aux
A purely visual mix-up. auto (/ˈɔːtəʊ/) and aux (/ˈɔks/) are said differently, so reading them aloud is the quickest way to catch the wrong one. On the page they stay close: they differ by 1 letter(s) in length. Our composite confusion score for this pair is 19275, derived from the frequency rank of both members and their visual similarity.
auto is recorded at frequency rank #3,099, classified as anadj, pronounced /ˈɔːtəʊ/. aux is at rank #16,176, tagged as anadj, pronounced /ˈɔks/.
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 19275, this pair ranks #439,295 of 530,003 scored English confusable pairs - a relatively easy-to-tell-apart pair.
Orthographic DNA of auto vs aux
Shared letters: au. Private to "auto": ot. Private to "aux": x.
"auto" · 4 letters · shape VVCV · "aux" · 3 letters · shape VVC
Known mistypes of this pair
- auto ← atuo · auot · autto · uato
Frequently Asked Questions
Can "auto" and "aux" be used interchangeably?
Frequency check: "auto" vs "aux" - which ranks higher?
What to do next
Pronunciation already separates them, if the page still looks alike, the dictionary links below settle it.
- Full dictionary entry for "auto" with definition, IPA, and generated misspellings. Word entry
- Full dictionary entry for "aux" - compare definitions side by side with the headword page. Word entry
- This pair ranks #439,295 of 530,003 scored English confusable pairs in this corpus vintage. Corpus statistics
- "auto" and "aux" also get mixed up with nearby pairs, the highest-scored neighbour is "amb vs aux". 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 #439,295 of 530,003 scored English pairs, corpus vintage 2026-09-03, not spelling advice.