a1vsasConfusable pair

Quick tell: a1 is a adjective, as is an adverb, so they fill different roles in a sentence.

Which to use

“a1” is an adjective and “as” is an adverb - they look or sound alike but fill different roles in a sentence.

#12,173
“a1” frequency rank
#18
“as” frequency rank
12191
confusion score

Side-by-Side Comparison

Feature a1 as
Definition first rate or excellent To such an extent or degree; to the same extent or degree.

Letter map: a1 vs as

Shared letters muted; letters that set a1 and as apart highlighted. Shared run: 1.

2 ch
a1
2 ch
as

Part-of-speech tell for a1 / as

Our dataset has no pronunciation recorded for both members, so the reliable separator here is grammatical: a1 is anadjective and asanadverb. On the page they differ by a single letter - 1 in “a1” becomes s in “as”. Our composite confusion score for this pair is 12191, derived from the frequency rank of both members and their visual similarity.

a1 is recorded at frequency rank #12,173, classified as anadj. 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 12191, this pair ranks #482,937 of 530,003 scored English confusable pairs - a relatively easy-to-tell-apart pair.

Orthographic DNA of a1 vs as

Shared letters: a. Private to "a1": -. Private to "as": s.

"a1" · 1 letters · shape V  ·  "as" · 2 letters · shape VC

Frequently Asked Questions

Do "a1" and "as" mean the same thing in a sentence?
No - they are not even the same part of speech. "a1" is an adjective and "as" an adverb, so a sentence built for one is usually ungrammatical with the other.
In ordinary English text, does "a1" or "as" show up more?
"as" is the more common of the two: it sits at frequency rank #18 in our English list, against #12,173 for "a1". That is a wide gap, so in ordinary text the rarer spelling is the one worth double-checking.

After this comparison

Done with this confusable. These links stay specific to "a1" and "as".

  • Full dictionary entry for "a1" 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 #482,937 of 530,003 scored English confusable pairs in this corpus vintage. Corpus statistics
  • "a1" and "as" also get mixed up with nearby pairs, the highest-scored neighbour is "a1 vs amb". Nearby pair

Confusion rank #482,937 of 530,003 scored English pairs, corpus vintage 2026-09-03, not spelling advice.

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

Source: FrequencyWords open word-frequency list