Which to use
“fortify” is a verb and “forty” is a num - they look or sound alike but fill different roles in a sentence.
- #32,810
- “fortify” frequency rank
- #5,130
- “forty” frequency rank
- 37940
- confusion score
Side-by-Side Comparison
| Feature | fortify | forty |
|---|---|---|
| Definition | To give power, strength, or vigour to (oneself or someone, or to something); to strengthen. | The cardinal number occurring after thirty-nine and before forty-one, represented in Roman numerals as XL and in Arabic numerals as 40. |
Where the eye mixes fortify and forty
Muted = shared; highlighted = the visual trap. They share 5 letters in sequence. fortify runs 7 letters (CVCCVCV) against forty's 5 (CVCCV) - the length gap alone is often enough to separate them once you know to check it.
Visual trap between fortify and forty
These two trip readers on the page rather than in the ear: fortify is /ˈfɔːtɪfaɪ/ while forty is /ˈfɔːti/. Spoken aloud the problem disappears. In writing it persists, because they differ by 2 letter(s) in length, and the parts of speech differ too (verb vs num), which is usually the fastest check. Our composite confusion score for this pair is 37940, derived from the frequency rank of both members and their visual similarity.
fortify is recorded at frequency rank #32,810, classified as averb, pronounced /ˈfɔːtɪfaɪ/. forty is at rank #5,130, tagged as anum, pronounced /ˈfɔːti/.
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 37940, this pair ranks #290,205 of 530,003 scored English confusable pairs - roughly mid-pack for confusability.
Orthographic DNA of fortify vs forty
Shared letters: forty. Private to "fortify": i. Private to "forty": -.
"fortify" · 7 letters · shape CVCCVCV · "forty" · 5 letters · shape CVCCV
Known mistypes of this pair
Frequently Asked Questions
Can "fortify" and "forty" be used interchangeably?
Frequency check: "fortify" vs "forty" - which ranks higher?
Useful next steps
Pronunciation already separates them, if the page still looks alike, the dictionary links below settle it.
- Full dictionary entry for "fortify" with definition, IPA, and generated misspellings. Word entry
- Full dictionary entry for "forty" - compare definitions side by side with the headword page. Word entry
- This pair ranks #290,205 of 530,003 scored English confusable pairs in this corpus vintage. Corpus statistics
- "fortify" and "forty" also get mixed up with nearby pairs, the highest-scored neighbour is "forties vs fortify". 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 #290,205 of 530,003 scored English pairs, corpus vintage 2026-09-03, not spelling advice.