A4vsatWhat's the difference?

Quick tell: A4 is a name, at is a preposition, so they fill different roles in a sentence.

Which to use

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

#18,471
“A4” frequency rank
#21
“at” frequency rank
18492
confusion score

Side-by-Side Comparison

Feature A4 at
Definition A4 class, a class of steam locomotive used on the London and North Eastern Railway. In, near, or in the general vicinity of (a particular place).

Letter map: A4 vs at

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

2 ch
A4
2 ch
at

Spelling & Dictionary Insight

Our dataset has no pronunciation recorded for both members, so the reliable separator here is grammatical: A4 is aname and atapreposition. On the page they differ by a single letter - 4 in “A4” becomes t in “at”. Our composite confusion score for this pair is 18492, derived from the frequency rank of both members and their visual similarity.

A4 is recorded at frequency rank #18,471, classified as aname. at is at rank #21, tagged as aprep, pronounced /æt/.

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 18492, this pair ranks #444,540 of 530,003 scored English confusable pairs - a relatively easy-to-tell-apart pair.

Orthographic DNA of A4 vs at

Shared letters: a. Private to "A4": -. Private to "at": t.

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

Frequently Asked Questions

Can "A4" and "at" be used interchangeably?
No - they are not even the same part of speech. "A4" is a name and "at" a preposition, so a sentence built for one is usually ungrammatical with the other.
Which is more common, "A4" or "at"?
"at" is the more common of the two: it sits at frequency rank #21 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.

Source: Wiktionary (via kaikki.org) Structured Wiktionary extract

Source: FrequencyWords open word-frequency list