AufbauvsAusbausWhich spelling fits?

Which to use

“Aufbau” and “Ausbaus” are a confusable German pair: similar on the page, but distinct in meaning, check the gloss before you choose.

#2,189
“Aufbau” frequency rank
#37,369
“Ausbaus” frequency rank
39558
confusion score

Side-by-Side Comparison

Feature Aufbau Ausbaus
Definition der Vorgang des Aufbauens eines Gebäudes, eines Systems oder einer sonstwie gearteten Struktur Genitiv Singular des Substantivs Ausbau

Where the eye mixes Aufbau and Ausbaus

Muted = shared; highlighted = the visual trap. They share 5 letters in sequence. Aufbau runs 6 letters (VVCCVV) against Ausbaus's 7 (VVCCVVC) - the length gap alone is often enough to separate them once you know to check it.

6 ch
Aufbau
7 ch
Ausbaus

Visual trap between Aufbau and Ausbaus

A purely visual mix-up. Aufbau ([ˈaʊ̯fˌbaʊ̯]) and Ausbaus ([ˈaʊ̯sˌbaʊ̯s]) are said differently, so reading them aloud is the quickest way to catch the wrong one. On the page they stay close: they differ by 1 letter(s) in length. Our composite confusion score for this pair is 39558, derived from the frequency rank of both members and their visual similarity.

Aufbau is recorded at frequency rank #2,189, classified as anoun, pronounced [ˈaʊ̯fˌbaʊ̯]. Ausbaus is at rank #37,369, tagged as anoun, pronounced [ˈaʊ̯sˌbaʊ̯s].

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 39558, this pair ranks #1,533,438 of 2,006,359 scored German confusable pairs - a relatively easy-to-tell-apart pair.

Orthographic DNA of Aufbau vs Ausbaus

Shared letters: abu. Private to "Aufbau": f. Private to "Ausbaus": s.

"Aufbau" · 6 letters · shape VVCCVV  ·  "Ausbaus" · 7 letters · shape VVCCVVC

Known mistypes of this pair

  • Aufbau ← afubau · aubfau · aufabu · aufbbau · aufbua · auffbau · uafbau
  • Ausbaus ← asubaus · aubsaus · ausabus · ausbasu · ausbauss · ausbbaus · ausbuas · aussbaus

Frequently Asked Questions

Do "Aufbau" and "Ausbaus" mean the same thing in a sentence?
No. They are said differently ([ˈaʊ̯fˌbaʊ̯] versus [ˈaʊ̯sˌbaʊ̯s]) and carry different meanings; reading the sentence aloud is usually enough to catch the wrong one.
In ordinary German text, does "Aufbau" or "Ausbaus" show up more?
"Aufbau" is the more common of the two: it sits at frequency rank #2,189 in our German list, against #37,369 for "Ausbaus". That is a wide gap, so in ordinary text the rarer spelling is the one worth double-checking.

After this comparison

Eye-level mix-up between "Aufbau" and "Ausbaus" is sorted above. Next: full entries or other pairs that share a letter shape.

  • Full dictionary entry for "Aufbau" with definition, IPA, and generated misspellings. Word entry
  • Full dictionary entry for "Ausbaus" - compare definitions side by side with the headword page. Word entry
  • This pair ranks #1,533,438 of 2,006,359 scored German confusable pairs in this corpus vintage. Corpus statistics
  • "Aufbau" and "Ausbaus" also get mixed up with nearby pairs, the highest-scored neighbour is "Ausbaus vs Auslauf". 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 #1,533,438 of 2,006,359 scored German pairs, corpus vintage 2026-09-03, not spelling advice.

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

Source: FrequencyWords open word-frequency list