ad vs así, What's the Difference?

Which to use

“ad” is a noun and “así” is an adverb - they look or sound alike but fill different roles in a sentence.

#5,365
“ad” frequency rank: #55
“así” frequency rank: 5420
confusion score

Side-by-Side Comparison

Feature	ad	así
Definition	Nombre.	De este modo o forma.

Where the eye mixes ad and así

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

2 ch

3 ch

así

Why the eye confuses ad with así

These two trip readers on the page rather than in the ear: ad is [ɑd] while así is [aˈsi]. Spoken aloud the problem disappears. In writing it persists, because they differ by 1 letter(s) in length, and the parts of speech differ too (noun vs adverb), which is usually the fastest check. Our composite confusion score for this pair is 5420, derived from the frequency rank of both members and their visual similarity.

ad is recorded at frequency rank #5,365, classified as anoun, pronounced [ɑd]. así is at rank #55, tagged as anadv, pronounced [aˈsi].

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 5420, this pair ranks #313,672 of 323,831 scored Spanish confusable pairs - a relatively easy-to-tell-apart pair.

Orthographic DNA of ad vs así

Shared letters: a. Private to "ad": d. Private to "así": sí.

"ad" · 2 letters · shape VC · "así" · 3 letters · shape VCV

Frequently Asked Questions

Is swapping "ad" for "así" ever safe?

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

In ordinary Spanish text, does "ad" or "así" show up more?

"así" is the more common of the two: it sits at frequency rank #55 in our Spanish list, against #5,365 for "ad". That is a wide gap, so in ordinary text the rarer spelling is the one worth double-checking.

Useful next steps

Visual near-miss handled. Browse the word pages or a neighbour when the next look-alike shows up.

Full dictionary entry for "ad" with definition, IPA, and generated misspellings. Word entry
Full dictionary entry for "así" - compare definitions side by side with the headword page. Word entry
This pair ranks #313,672 of 323,831 scored Spanish confusable pairs in this corpus vintage. Corpus statistics
"ad" and "así" also get mixed up with nearby pairs, the highest-scored neighbour is "abed vs ad". Nearby pair

Confusion rank #313,672 of 323,831 scored Spanish pairs, corpus vintage 2026-09-03, not spelling advice.