Which to use
“assert” and “assure” are a confusable English pair: similar on the page, but distinct in meaning, check the gloss before you choose.
- #12,544
- “assert” frequency rank
- #6,438
- “assure” frequency rank
- 18982
- confusion score
Side-by-Side Comparison
| Feature | assert | assure |
|---|---|---|
| Definition | To declare with assurance or plainly and strongly; to state positively. | To make sure and secure; ensure. |
Where the eye mixes assert and assure
Muted = shared; highlighted = the visual trap. They share 4 letters in sequence.
Look-alike desk: assert vs assure
A purely visual mix-up. assert (/əˈsɜːt/) and assure (/əˈʃɔː(ɹ)/) are said differently, so reading them aloud is the quickest way to catch the wrong one. On the page they stay close: they share most of their letters but differ in 2 positions. Our composite confusion score for this pair is 18982, derived from the frequency rank of both members and their visual similarity.
assert is recorded at frequency rank #12,544, classified as averb, pronounced /əˈsɜːt/. assure is at rank #6,438, tagged as averb, pronounced /əˈʃɔː(ɹ)/.
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 18982, this pair ranks #441,282 of 530,003 scored English confusable pairs - a relatively easy-to-tell-apart pair.
Orthographic DNA of assert vs assure
Shared letters: aers. Private to "assert": t. Private to "assure": u.
"assert" · 6 letters · shape VCCVCC · "assure" · 6 letters · shape VCCVCV
Known mistypes of this pair
Frequently Asked Questions
Can "assert" and "assure" be used interchangeably?
In ordinary English text, does "assert" or "assure" show up more?
After this comparison
Eye-level mix-up between "assert" and "assure" is sorted above. Next: full entries or other pairs that share a letter shape.
- Full dictionary entry for "assert" with definition, IPA, and generated misspellings. Word entry
- Full dictionary entry for "assure" - compare definitions side by side with the headword page. Word entry
- This pair ranks #441,282 of 530,003 scored English confusable pairs in this corpus vintage. Corpus statistics
- "assert" and "assure" also get mixed up with nearby pairs, the highest-scored neighbour is "assuage vs assure". 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 #441,282 of 530,003 scored English pairs, corpus vintage 2026-09-03, not spelling advice.