attavsauthTell them apart

Quick tell: atta is a contraction, auth is a noun, so they fill different roles in a sentence.

Which to use

“atta” is a contraction and “auth” is a noun - they look or sound alike but fill different roles in a sentence.

#29,174
“atta” frequency rank
#30,696
“auth” frequency rank
59870
confusion score

Side-by-Side Comparison

Feature atta auth
Definition that's the; that's a Abbreviation of authentication.

Letter map: atta vs auth

Shared letters muted; letters that set atta and auth apart highlighted. Shared run: 2.

4 ch
atta
4 ch
auth

Role in the sentence - atta and auth

Our dataset has no pronunciation recorded for both members, so the reliable separator here is grammatical: atta is acontraction and authanoun. On the page they share most of their letters but differ in 2 positions. Our composite confusion score for this pair is 59870, derived from the frequency rank of both members and their visual similarity.

atta is recorded at frequency rank #29,174, classified as acontraction. auth is at rank #30,696, tagged as anoun.

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 59870, this pair ranks #103,600 of 530,003 scored English confusable pairs - among the most confusable pairs.

Orthographic DNA of atta vs auth

Shared letters: at. Private to "atta": -. Private to "auth": hu.

"atta" · 4 letters · shape VCCV  ·  "auth" · 4 letters · shape VVCC

Known mistypes of this pair

  • attaatat
  • authatuh · auht · authh · autth

Frequently Asked Questions

Is swapping "atta" for "auth" ever safe?
No - they are not even the same part of speech. "atta" is a contraction and "auth" a noun, so a sentence built for one is usually ungrammatical with the other.
In ordinary English text, does "atta" or "auth" show up more?
"atta" is the more common of the two: it sits at frequency rank #29,174 in our English list, against #30,696 for "auth". The two are close in frequency, so neither is a safe default; check the meaning rather than guessing.

After this comparison

You've compared "atta" and "auth". Here's where to go from here.

  • Full dictionary entry for "atta" with definition, IPA, and generated misspellings. Word entry
  • Full dictionary entry for "auth" - compare definitions side by side with the headword page. Word entry
  • This pair ranks #103,600 of 530,003 scored English confusable pairs in this corpus vintage. Corpus statistics
  • "atta" and "auth" also get mixed up with nearby pairs, the highest-scored neighbour is "Asta vs auth". Nearby pair
  • Recorded mistypes exist for at least one side of this pair, useful when a spell-checker or OCR lands on the wrong form. See mistypes

Confusion rank #103,600 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