Ruby is a coat-color name pretending to be a gemstone name. With 2,339 entries at rank #28, she shows up almost exclusively on red, chestnut, and copper-coated dogs — Vizslas, Irish Setters, the deep-red Cocker Spaniels, and the warm-side Cavaliers. Owners who pick Ruby say they're choosing it for the gem; the data says they're choosing it for the dog's color. Both are true, but only one is doing the actual selection work.
The Cavalier King Charles connection
The Cavalier breed standard recognizes four colors, one of which is named "Ruby" — a solid rich-red coat. Owners of ruby Cavaliers reach for Ruby as a name at a meaningfully higher rate than other Cavalier color owners, and that's not a coincidence. The breed's color terminology has invaded the breed's naming patterns. Compare this with Yorkies, where the breed-recognized colors don't have name equivalents and the naming patterns are more random.
What's worth noticing is that Ruby barely appears on black or white dogs in our dataset. The color-matching is sharper for Ruby than for almost any other color-adjacent name in the top 50. Penny does similar work but spreads more loosely; Ruby is more disciplined.
Sound profile
Two syllables, hard R opening, soft B in the middle, clipped "ee" ending. Ruby is recall-friendly without being sharp — the R does most of the carrying work, and the rest of the name softens around it. Active-breed owners get acceptable park-distance performance; small-breed owners get a name that reads warm at home. That dual-register flexibility is part of why the name has stayed steady across the breed range it covers.
The baby version is in the top 100
Ruby returned to the SSA charts in the late 1990s after decades in the wilderness and is now in the top 100 for girls. The pet trajectory has climbed alongside but more slowly. The baby and pet versions are running close enough that household-overlap is a real concern, especially in households where the dog was named first and the child arrived second. Most parents I've heard from in this situation simply accept it. The baby Ruby page has the SSA detail.