As vs au, What's the Difference?

Which to use

“As” is a name and “au” is an article - they look or sound alike but fill different roles in a sentence.

#135
“As” frequency rank: #24
“au” frequency rank: 159
confusion score

Side-by-Side Comparison

Feature	As	au
Definition	Commune de la province de Limbourg de la région flamande de Belgique.	Contraction de la préposition à et de l'article défini le.

Where the eye mixes As and au

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

2 ch

Why the eye confuses As with au

These two trip readers on the page rather than in the ear: As is \as\ while au is \o\. Spoken aloud the problem disappears. In writing it persists, because they differ by a single letter - s in “As” becomes u in “au”, and the parts of speech differ too (name vs article), which is usually the fastest check. Our composite confusion score for this pair is 159, derived from the frequency rank of both members and their visual similarity.

As is recorded at frequency rank #135, classified as aname, pronounced \as\. au is at rank #24, tagged as anarticle, pronounced \o\.

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 159, this pair ranks #440,040 of 440,172 scored French confusable pairs - a relatively easy-to-tell-apart pair.

Orthographic DNA of As vs au

Shared letters: a. Private to "As": s. Private to "au": u.

"As" · 2 letters · shape VC · "au" · 2 letters · shape VV

Frequently Asked Questions

Is swapping "As" for "au" ever safe?

No - they are not even the same part of speech. "As" is a name and "au" an article, so a sentence built for one is usually ungrammatical with the other.

In ordinary French text, does "As" or "au" show up more?

"au" is the more common of the two: it sits at frequency rank #24 in our French list, against #135 for "As". The two are close in frequency, so neither is a safe default; check the meaning rather than guessing.

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 "As" with definition, IPA, and generated misspellings. Word entry
Full dictionary entry for "au" - compare definitions side by side with the headword page. Word entry
This pair ranks #440,040 of 440,172 scored French confusable pairs in this corpus vintage. Corpus statistics
"As" and "au" also get mixed up with nearby pairs, the highest-scored neighbour is "As vs aves". Nearby pair

Confusion rank #440,040 of 440,172 scored French pairs, corpus vintage 2026-09-03, not spelling advice.