rubyvsrunWhat's the difference?

Quick tell: ruby is a noun, run is a verb, so they fill different roles in a sentence.

Which to use

“ruby” is a noun and “run” is a verb - they look or sound alike but fill different roles in a sentence.

#7,386
“ruby” frequency rank
#309
“run” frequency rank
7695
confusion score

Side-by-Side Comparison

Feature ruby run
Definition A clear, deep, red variety of corundum, valued as a precious stone. To move swiftly.

Where the eye mixes ruby and run

Muted = shared; highlighted = the visual trap. They share 2 letters in sequence.

4 ch
ruby
3 ch
run

Visual trap between ruby and run

These two trip readers on the page rather than in the ear: ruby is /ˈɹuː.bi/ while run is /ɹʌn/. Spoken aloud the problem disappears. In writing it persists, because they differ by 1 letter(s) in length, and the parts of speech differ too (noun vs verb), which is usually the fastest check. Our composite confusion score for this pair is 7695, derived from the frequency rank of both members and their visual similarity.

ruby is recorded at frequency rank #7,386, classified as anoun, pronounced /ˈɹuː.bi/. run is at rank #309, tagged as averb, pronounced /ɹʌn/.

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 7695, this pair ranks #505,989 of 530,003 scored English confusable pairs - a relatively easy-to-tell-apart pair.

Orthographic DNA of ruby vs run

Shared letters: ru. Private to "ruby": by. Private to "run": n.

"ruby" · 4 letters · shape CVCV  ·  "run" · 3 letters · shape CVC

Known mistypes of this pair

  • rubyrbuy · rruby · rubby · rubyy · ruyb · urby

Frequently Asked Questions

Is swapping "ruby" for "run" ever safe?
No - they are not even the same part of speech. "ruby" is a noun and "run" a verb, so a sentence built for one is usually ungrammatical with the other.
Frequency check: "ruby" vs "run" - which ranks higher?
"run" is the more common of the two: it sits at frequency rank #309 in our English list, against #7,386 for "ruby". That is a wide gap, so in ordinary text the rarer spelling is the one worth double-checking.

After this comparison

Visual near-miss handled. Browse the word pages or a neighbour when the next look-alike shows up.

  • Full dictionary entry for "ruby" with definition, IPA, and generated misspellings. Word entry
  • Full dictionary entry for "run" - compare definitions side by side with the headword page. Word entry
  • This pair ranks #505,989 of 530,003 scored English confusable pairs in this corpus vintage. Corpus statistics
  • "ruby" and "run" also get mixed up with nearby pairs, the highest-scored neighbour is "Rua vs ruby". 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 #505,989 of 530,003 scored English pairs, corpus vintage 2026-09-03, not spelling advice.

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

Source: FrequencyWords open word-frequency list