confidentialvsconfidentiallyWhat's the difference?

Quick tell: confidential is a adjective, confidentially is an adverb, so they fill different roles in a sentence.

Which to use

“confidential” is an adjective and “confidentially” is an adverb - they look or sound alike but fill different roles in a sentence.

#8,265
“confidential” frequency rank
#46,391
“confidentially” frequency rank
54656
confusion score

Side-by-Side Comparison

Feature confidential confidentially
Definition Kept, or meant to be kept, secret within a certain circle of persons; not intended to be known publicly In a confidential manner.

Letter map: confidential vs confidentially

Shared letters muted; letters that set confidential and confidentially apart highlighted. Shared run: 12. confidential runs 12 letters (CVCCVCVCCVVC) against confidentially's 14 (CVCCVCVCCVVCCV) - the length gap alone is often enough to separate them once you know to check it.

12 ch
confidential
14 ch
confidentially

Role in the sentence - confidential and confidentially

Our dataset has no pronunciation recorded for both members, so the reliable separator here is grammatical: confidential is anadjective and confidentiallyanadverb. On the page they differ by 2 extra letter(s) - “confidential” sits inside “confidentially”. Our composite confusion score for this pair is 54656, derived from the frequency rank of both members and their visual similarity.

confidential is recorded at frequency rank #8,265, classified as anadj, pronounced /ˌkɑːnfɪˈdɛnʃl/. confidentially is at rank #46,391, tagged as anadv.

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 54656, this pair ranks #139,409 of 530,003 scored English confusable pairs - roughly mid-pack for confusability.

Orthographic DNA of confidential vs confidentially

Shared letters: acdefilnot. Private to "confidential": -. Private to "confidentially": y.

"confidential" · 12 letters · shape CVCCVCVCCVVC  ·  "confidentially" · 14 letters · shape CVCCVCVCCVVCCV

Known mistypes of this pair

  • confidential ← cconfidential · cnofidential · cofnidential · confdiential · conffidential · confiddential · confidenital · confidenntial
  • confidentially ← cconfidentially · cnofidentially · cofnidentially · confdientially · conffidentially · confiddentially · confidenitally · confidenntially

Frequently Asked Questions

Can "confidential" and "confidentially" be used interchangeably?
No - they are not even the same part of speech. "confidential" is an adjective and "confidentially" an adverb, so a sentence built for one is usually ungrammatical with the other.
Which is more common, "confidential" or "confidentially"?
"confidential" is the more common of the two: it sits at frequency rank #8,265 in our English list, against #46,391 for "confidentially". The two are close in frequency, so neither is a safe default; check the meaning rather than guessing.

After this comparison

Pair "confidential" vs "confidentially" is on the table, pick a follow-up below.

  • Full dictionary entry for "confidential" with definition, IPA, and generated misspellings. Word entry
  • Full dictionary entry for "confidentially" - compare definitions side by side with the headword page. Word entry
  • This pair ranks #139,409 of 530,003 scored English confusable pairs in this corpus vintage. Corpus statistics
  • "confidential" and "confidentially" also get mixed up with nearby pairs, the highest-scored neighbour is "confidentiality vs confidentially". 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 #139,409 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