Which to use
“successful” is an adjective and “successfully” is an adverb - they look or sound alike but fill different roles in a sentence.
- #1,238
- “successful” frequency rank
- #3,337
- “successfully” frequency rank
- 4575
- confusion score
Side-by-Side Comparison
| Feature | successful | successfully |
|---|---|---|
| Definition | Resulting in success; assuring or promoting success; accomplishing what was proposed; having the desired effect. | In a successful manner; with success; without failing. |
Where the eye mixes successful and successfully
Muted = shared; highlighted = the visual trap. They share 10 letters in sequence.
Why the eye confuses successful with successfully
These two trip readers on the page rather than in the ear: successful is /səkˈsɛs.fəl/ while successfully is /səkˈsɛs.fə.li/. Spoken aloud the problem disappears. In writing it persists, because they differ by 2 extra letter(s) - “successful” sits inside “successfully”, and the parts of speech differ too (adjective vs adverb), which is usually the fastest check. Our composite confusion score for this pair is 4575, derived from the frequency rank of both members and their visual similarity.
successful is recorded at frequency rank #1,238, classified as anadj, pronounced /səkˈsɛs.fəl/. successfully is at rank #3,337, tagged as anadv, pronounced /səkˈsɛs.fə.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 4575, this pair ranks #518,447 of 530,003 scored English confusable pairs - a relatively easy-to-tell-apart pair.
Orthographic DNA of successful vs successfully
Shared letters: ceflsu. Private to "successful": -. Private to "successfully": y.
"successful" · 10 letters · shape CVCCVCCCVC · "successfully" · 12 letters · shape CVCCVCCCVCCV
Known mistypes of this pair
- successful ← scucessful · ssuccessful · succesfsul · succesful · successfful · successflu · successfull · successufl
- successfully ← scucessfully · ssuccessfully · succesfsully · succesfully · successffully · successfluly · successfullyy · successfuly
Frequently Asked Questions
Is swapping "successful" for "successfully" ever safe?
Which is more common, "successful" or "successfully"?
What to do next
Pronunciation already separates them, if the page still looks alike, the dictionary links below settle it.
- Full dictionary entry for "successful" with definition, IPA, and generated misspellings. Word entry
- Full dictionary entry for "successfully" - compare definitions side by side with the headword page. Word entry
- This pair ranks #518,447 of 530,003 scored English confusable pairs in this corpus vintage. Corpus statistics
- 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 #518,447 of 530,003 scored English pairs, corpus vintage 2026-09-03, not spelling advice.