rvsroiWhat's the difference?

Quick tell: r is a character, roi is a noun, so they fill different roles in a sentence.

Which to use

“r” is a character and “roi” is a noun - they look or sound alike but fill different roles in a sentence.

#637
“r” frequency rank
#547
“roi” frequency rank
1184
confusion score

Side-by-Side Comparison

Feature r roi
Definition Dix-huitième lettre et quatorzième consonne de l’alphabet (minuscule). Titre porté par celui qui règne sur un peuple, un État, en particulier un État monarchique, et qui tient sa fonction de l’hérédité ou de l’élection ; celui qui est à la tête d’un royaume.

Where the eye mixes r and roi

Muted = shared; highlighted = the visual trap. They share 1 letter in sequence.

1 ch
r
3 ch
roi

Spelling & Dictionary Insight

These two trip readers on the page rather than in the ear: r is \ɛʁ\ while roi is \ʁwa\. Spoken aloud the problem disappears. In writing it persists, because they differ by 2 extra letter(s) - “r” sits inside “roi”, and the parts of speech differ too (character vs noun), which is usually the fastest check. Our composite confusion score for this pair is 1184, derived from the frequency rank of both members and their visual similarity.

r is recorded at frequency rank #637, classified as acharacter, pronounced \ɛʁ\. roi is at rank #547, tagged as anoun, pronounced \ʁwa\.

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 1184, this pair ranks #438,478 of 440,172 scored French confusable pairs - a relatively easy-to-tell-apart pair.

Orthographic DNA of r vs roi

Shared letters: r. Private to "r": -. Private to "roi": io.

"r" · 1 letters · shape C  ·  "roi" · 3 letters · shape CVV

Frequently Asked Questions

Can "r" and "roi" be used interchangeably?
No - they are not even the same part of speech. "r" is a character and "roi" a noun, so a sentence built for one is usually ungrammatical with the other.
Which is more common, "r" or "roi"?
"roi" is the more common of the two: it sits at frequency rank #547 in our French list, against #637 for "r". The two are close in frequency, so neither is a safe default; check the meaning rather than guessing.

Source: Wiktionary (via kaikki.org) Structured Wiktionary extract

Source: FrequencyWords open word-frequency list