optvsopusWhich spelling fits?

Quick tell: opt is a verb, opus is a noun, so they fill different roles in a sentence.

Which to use

“opt” is a verb and “opus” is a noun - they look or sound alike but fill different roles in a sentence.

#8,325
“opt” frequency rank
#23,619
“opus” frequency rank
31944
confusion score

Side-by-Side Comparison

Feature opt opus
Definition To choose; select. A work of music or set of works with a specified rank in an ordering of a composer's complete published works.

Where the eye mixes opt and opus

Muted = shared; highlighted = the visual trap. They share 2 letters in sequence.

3 ch
opt
4 ch
opus

Visual trap between opt and opus

These two trip readers on the page rather than in the ear: opt is /ɒpt/ while opus is /ˈəʊpəs/. 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 (verb vs noun), which is usually the fastest check. Our composite confusion score for this pair is 31944, derived from the frequency rank of both members and their visual similarity.

opt is recorded at frequency rank #8,325, classified as averb, pronounced /ɒpt/. opus is at rank #23,619, tagged as anoun, pronounced /ˈəʊpəs/.

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 31944, this pair ranks #341,896 of 530,003 scored English confusable pairs - roughly mid-pack for confusability.

Orthographic DNA of opt vs opus

Shared letters: op. Private to "opt": t. Private to "opus": su.

"opt" · 3 letters · shape VCC  ·  "opus" · 4 letters · shape VCVC

Known mistypes of this pair

  • opusoppus · opsu · opuss · oups · pous

Frequently Asked Questions

Can "opt" and "opus" be used interchangeably?
No - they are not even the same part of speech. "opt" is a verb and "opus" a noun, so a sentence built for one is usually ungrammatical with the other.
In ordinary English text, does "opt" or "opus" show up more?
"opt" is the more common of the two: it sits at frequency rank #8,325 in our English list, against #23,619 for "opus". The two are close in frequency, so neither is a safe default; check the meaning rather than guessing.

What to do next

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

  • Full dictionary entry for "opt" with definition, IPA, and generated misspellings. Word entry
  • Full dictionary entry for "opus" - compare definitions side by side with the headword page. Word entry
  • This pair ranks #341,896 of 530,003 scored English confusable pairs in this corpus vintage. Corpus statistics
  • "opt" and "opus" also get mixed up with nearby pairs, the highest-scored neighbour is "opus vs OWS". 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 #341,896 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