A4 vs as, What's the Difference?

Which to use

“A4” is a name and “as” is an adverb - they look or sound alike but fill different roles in a sentence.

#18,471
“A4” frequency rank: #18
“as” frequency rank: 18489
confusion score

Side-by-Side Comparison

Feature	A4	as
Definition	A4 class, a class of steam locomotive used on the London and North Eastern Railway.	To such an extent or degree; to the same extent or degree.

Letter map: A4 vs as

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

2 ch

Role in the sentence - A4 and as

Our dataset has no pronunciation recorded for both members, so the reliable separator here is grammatical: A4 is aname and asanadverb. On the page they differ by a single letter - 4 in “A4” becomes s in “as”. Our composite confusion score for this pair is 18489, derived from the frequency rank of both members and their visual similarity.

A4 is recorded at frequency rank #18,471, classified as aname. as is at rank #18, tagged as anadv, pronounced /əz/.

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 18489, this pair ranks #444,576 of 530,003 scored English confusable pairs - a relatively easy-to-tell-apart pair.

Orthographic DNA of A4 vs as

Shared letters: a. Private to "A4": -. Private to "as": s.

"A4" · 1 letters · shape V · "as" · 2 letters · shape VC

Frequently Asked Questions

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

No - they are not even the same part of speech. "A4" is a name and "as" an adverb, so a sentence built for one is usually ungrammatical with the other.

In ordinary English text, does "A4" or "as" show up more?

"as" is the more common of the two: it sits at frequency rank #18 in our English list, against #18,471 for "A4". That is a wide gap, so in ordinary text the rarer spelling is the one worth double-checking.

What to do next

You've compared "A4" and "as". Here's where to go from here.

Full dictionary entry for "A4" with definition, IPA, and generated misspellings. Word entry
Full dictionary entry for "as" - compare definitions side by side with the headword page. Word entry
This pair ranks #444,576 of 530,003 scored English confusable pairs in this corpus vintage. Corpus statistics
"A4" and "as" also get mixed up with nearby pairs, the highest-scored neighbour is "A4 vs amb". Nearby pair

Confusion rank #444,576 of 530,003 scored English pairs, corpus vintage 2026-09-03, not spelling advice.