Which to use
“efficient” is an adjective and “efficiently” is an adverb - they look or sound alike but fill different roles in a sentence.
- #3,484
- “efficient” frequency rank
- #9,739
- “efficiently” frequency rank
- 13223
- confusion score
Side-by-Side Comparison
| Feature | efficient | efficiently |
|---|---|---|
| Definition | Making good, thorough, or careful use of resources; not consuming extra. Especially, making good use of time or energy. | In an efficient manner. |
Letter map: efficient vs efficiently
Shared letters muted; letters that set efficient and efficiently apart highlighted. Shared run: 9.
Grammar separator: efficient vs efficiently
Our dataset has no pronunciation recorded for both members, so the reliable separator here is grammatical: efficient is anadjective and efficientlyanadverb. On the page they differ by 2 extra letter(s) - “efficient” sits inside “efficiently”. Our composite confusion score for this pair is 13223, derived from the frequency rank of both members and their visual similarity.
efficient is recorded at frequency rank #3,484, classified as anadj, pronounced /ɪˈfɪʃənt/. efficiently is at rank #9,739, 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 13223, this pair ranks #477,053 of 530,003 scored English confusable pairs - a relatively easy-to-tell-apart pair.
Orthographic DNA of efficient vs efficiently
Shared letters: cefint. Private to "efficient": -. Private to "efficiently": ly.
"efficient" · 9 letters · shape VCCVCVVCC · "efficiently" · 11 letters · shape VCCVCVVCCCV
Known mistypes of this pair
- efficient ← effciient · efficcient · efficeint · efficiennt · efficientt · efficietn · efficinet · effiicent
- efficiently ← effciiently · efficciently · efficeintly · efficienlty · efficienntly · efficientlly · efficientlyy · efficienttly
Frequently Asked Questions
Is swapping "efficient" for "efficiently" ever safe?
In ordinary English text, does "efficient" or "efficiently" show up more?
Useful next steps
Done with this confusable. These links stay specific to "efficient" and "efficiently".
- Full dictionary entry for "efficient" with definition, IPA, and generated misspellings. Word entry
- Full dictionary entry for "efficiently" - compare definitions side by side with the headword page. Word entry
- This pair ranks #477,053 of 530,003 scored English confusable pairs in this corpus vintage. Corpus statistics
- "efficient" and "efficiently" also get mixed up with nearby pairs, the highest-scored neighbour is "efficiency vs efficiently". 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 #477,053 of 530,003 scored English pairs, corpus vintage 2026-09-03, not spelling advice.