mistakenvsmistakenlyWhat's the difference?

Quick tell: mistaken is a verb, mistakenly is an adverb, so they fill different roles in a sentence.

Which to use

“mistaken” is a verb and “mistakenly” is an adverb - they look or sound alike but fill different roles in a sentence.

#7,363
“mistaken” frequency rank
#16,077
“mistakenly” frequency rank
23440
confusion score

Side-by-Side Comparison

Feature mistaken mistakenly
Definition past participle of mistake Wrongly; erroneously.

Where the eye mixes mistaken and mistakenly

Muted = shared; highlighted = the visual trap. They share 8 letters in sequence. mistaken runs 8 letters (CVCCVCVC) against mistakenly's 10 (CVCCVCVCCV) - the length gap alone is often enough to separate them once you know to check it.

8 ch
mistaken
10 ch
mistakenly

Why the eye confuses mistaken with mistakenly

These two trip readers on the page rather than in the ear: mistaken is /mɪˈsteɪkn̩/ while mistakenly is /mɪˈsteɪ.kən.li/. Spoken aloud the problem disappears. In writing it persists, because they differ by 2 extra letter(s) - “mistaken” sits inside “mistakenly”, and the parts of speech differ too (verb vs adverb), which is usually the fastest check. Our composite confusion score for this pair is 23440, derived from the frequency rank of both members and their visual similarity.

mistaken is recorded at frequency rank #7,363, classified as averb, pronounced /mɪˈsteɪkn̩/. mistakenly is at rank #16,077, tagged as anadv, pronounced /mɪˈsteɪ.kən.li/.

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 23440, this pair ranks #409,248 of 530,003 scored English confusable pairs - a relatively easy-to-tell-apart pair.

Orthographic DNA of mistaken vs mistakenly

Shared letters: aeikmnst. Private to "mistaken": -. Private to "mistakenly": ly.

"mistaken" · 8 letters · shape CVCCVCVC  ·  "mistakenly" · 10 letters · shape CVCCVCVCCV

Known mistypes of this pair

  • mistaken ← imstaken · misatken · misstaken · mistaekn · mistakenn · mistakken · mistakne · mistkaen
  • mistakenly ← imstakenly · misatkenly · misstakenly · mistaeknly · mistakelny · mistakenlly · mistakenlyy · mistakennly

Frequently Asked Questions

Can "mistaken" and "mistakenly" be used interchangeably?
No - they are not even the same part of speech. "mistaken" is a verb and "mistakenly" an adverb, so a sentence built for one is usually ungrammatical with the other.
Frequency check: "mistaken" vs "mistakenly" - which ranks higher?
"mistaken" is the more common of the two: it sits at frequency rank #7,363 in our English list, against #16,077 for "mistakenly". 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 "mistaken" with definition, IPA, and generated misspellings. Word entry
  • Full dictionary entry for "mistakenly" - compare definitions side by side with the headword page. Word entry
  • This pair ranks #409,248 of 530,003 scored English confusable pairs in this corpus vintage. Corpus statistics
  • "mistaken" and "mistakenly" also get mixed up with nearby pairs, the highest-scored neighbour is "mistaken vs mistaking". 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 #409,248 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