openvsoppWhat's the difference?

Quick tell: open is a adjective, opp is a preposition, so they fill different roles in a sentence.

Which to use

“open” is an adjective and “opp” is a preposition - they look or sound alike but fill different roles in a sentence.

#314
“open” frequency rank
#35,442
“opp” frequency rank
35756
confusion score

Side-by-Side Comparison

Feature open opp
Definition Physically unobstructed, uncovered, etc. Abbreviation of opposite.

Where the eye mixes open and opp

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

4 ch
open
3 ch
opp

Why the eye confuses open with opp

These two trip readers on the page rather than in the ear: open is /ˈəʊ.pən/ while opp is /ɒp/. 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 (adjective vs preposition), which is usually the fastest check. Our composite confusion score for this pair is 35756, derived from the frequency rank of both members and their visual similarity.

open is recorded at frequency rank #314, classified as anadj, pronounced /ˈəʊ.pən/. opp is at rank #35,442, tagged as aprep, pronounced /ɒp/.

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 35756, this pair ranks #309,206 of 530,003 scored English confusable pairs - roughly mid-pack for confusability.

Orthographic DNA of open vs opp

Shared letters: op. Private to "open": en. Private to "opp": -.

"open" · 4 letters · shape VCVC  ·  "opp" · 3 letters · shape VCC

Known mistypes of this pair

  • openoepn · openn · opne · oppen · poen

Frequently Asked Questions

Can "open" and "opp" be used interchangeably?
No - they are not even the same part of speech. "open" is an adjective and "opp" a preposition, so a sentence built for one is usually ungrammatical with the other.
Which is more common, "open" or "opp"?
"open" is the more common of the two: it sits at frequency rank #314 in our English list, against #35,442 for "opp". 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 "open" with definition, IPA, and generated misspellings. Word entry
  • Full dictionary entry for "opp" - compare definitions side by side with the headword page. Word entry
  • This pair ranks #309,206 of 530,003 scored English confusable pairs in this corpus vintage. Corpus statistics
  • "open" and "opp" also get mixed up with nearby pairs, the highest-scored neighbour is "omi vs opp". 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 #309,206 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