A3 vs A4, What's the Difference?

Which to use

“A3” is a noun and “A4” is a symbol - they look or sound alike but fill different roles in a sentence.

#20,334
“A3” frequency rank: #18,920
“A4” frequency rank: 39254
confusion score

Side-by-Side Comparison

Feature	A3	A4
Definition	Format de papier mesurant 420 mm × 297 mm.	Format de papier de 210 mm × 297 mm.

Letter map: A3 vs A4

Shared letters muted; letters that set A3 and A4 apart highlighted. Shared run: 1.

2 ch

Role in the sentence - A3 and A4

Our dataset has no pronunciation recorded for both members, so the reliable separator here is grammatical: A3 is anoun and A4asymbol. On the page they differ by a single letter - 3 in “A3” becomes 4 in “A4”. Our composite confusion score for this pair is 39254, derived from the frequency rank of both members and their visual similarity.

A3 is recorded at frequency rank #20,334, classified as anoun, pronounced \ɑ.tʁwa\. A4 is at rank #18,920, tagged as asymbol.

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 39254, this pair ranks #249,351 of 440,172 scored French confusable pairs - roughly mid-pack for confusability.

Orthographic DNA of A3 vs A4

Shared letters: a. Private to "A3": -. Private to "A4": -.

"A3" · 1 letters · shape V · "A4" · 1 letters · shape V

Frequently Asked Questions

Is swapping "A3" for "A4" ever safe?

No - they are not even the same part of speech. "A3" is a noun and "A4" a symbol, so a sentence built for one is usually ungrammatical with the other.

In ordinary French text, does "A3" or "A4" show up more?

"A4" is the more common of the two: it sits at frequency rank #18,920 in our French list, against #20,334 for "A3". The two are close in frequency, so neither is a safe default; check the meaning rather than guessing.

What to do next

Pair "A3" vs "A4" is on the table, pick a follow-up below.

Full dictionary entry for "A3" with definition, IPA, and generated misspellings. Word entry
Full dictionary entry for "A4" - compare definitions side by side with the headword page. Word entry
This pair ranks #249,351 of 440,172 scored French confusable pairs in this corpus vintage. Corpus statistics
"A3" and "A4" also get mixed up with nearby pairs, the highest-scored neighbour is "A3 vs aur". Nearby pair

Confusion rank #249,351 of 440,172 scored French pairs, corpus vintage 2026-09-03, not spelling advice.