AufbausvsAusbauWhich spelling fits?

Which to use

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

#34,521
“Aufbaus” frequency rank
#3,170
“Ausbau” frequency rank
37691
confusion score

Side-by-Side Comparison

Feature Aufbaus Ausbau
Definition Genitiv Singular des Substantivs Aufbau planmäßige Vergrößerung, Erweiterung von etwas Bestehendem

Where the eye mixes Aufbaus and Ausbau

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

7 ch
Aufbaus
6 ch
Ausbau

Look-alike desk: Aufbaus vs Ausbau

A purely visual mix-up. Aufbaus ([ˈaʊ̯fˌbaʊ̯s]) and Ausbau ([ˈaʊ̯sˌbaʊ̯]) 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 37691, derived from the frequency rank of both members and their visual similarity.

Aufbaus is recorded at frequency rank #34,521, classified as anoun, pronounced [ˈaʊ̯fˌbaʊ̯s]. Ausbau is at rank #3,170, tagged as anoun, pronounced [ˈaʊ̯sˌbaʊ̯].

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 37691, this pair ranks #1,583,573 of 2,006,359 scored German confusable pairs - a relatively easy-to-tell-apart pair.

Orthographic DNA of Aufbaus vs Ausbau

Shared letters: absu. Private to "Aufbaus": f. Private to "Ausbau": -.

"Aufbaus" · 7 letters · shape VVCCVVC  ·  "Ausbau" · 6 letters · shape VVCCVV

Known mistypes of this pair

  • Aufbaus ← afubaus · aubfaus · aufabus · aufbasu · aufbauss · aufbbaus · aufbuas · auffbaus
  • Ausbau ← asubau · aubsau · ausabu · ausbbau · ausbua · aussbau · uasbau

Frequently Asked Questions

Do "Aufbaus" and "Ausbau" mean the same thing in a sentence?
No. They are said differently ([ˈaʊ̯fˌbaʊ̯s] versus [ˈaʊ̯sˌbaʊ̯]) and carry different meanings; reading the sentence aloud is usually enough to catch the wrong one.
Frequency check: "Aufbaus" vs "Ausbau" - which ranks higher?
"Ausbau" is the more common of the two: it sits at frequency rank #3,170 in our German list, against #34,521 for "Aufbaus". That is a wide gap, so in ordinary text the rarer spelling is the one worth double-checking.

After this comparison

Pronunciation already separates them, if the page still looks alike, the dictionary links below settle it.

  • Full dictionary entry for "Aufbaus" with definition, IPA, and generated misspellings. Word entry
  • Full dictionary entry for "Ausbau" - compare definitions side by side with the headword page. Word entry
  • This pair ranks #1,583,573 of 2,006,359 scored German confusable pairs in this corpus vintage. Corpus statistics
  • "Aufbaus" and "Ausbau" also get mixed up with nearby pairs, the highest-scored neighbour is "Aufbaus vs Ausbaus". 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 #1,583,573 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