Penny is the copper-colored name. With 2,742 entries at rank #19, she shows up disproportionately on red-and-tan dogs — Vizslas, Cocker Spaniels, the warmer-coated Dachshunds, and Goldens whose coat sits on the deep end of the breed standard. Owners are matching the name to the coin, which is the most literal naming logic in the top 20.
Coat color as naming signal
Pet naming is full of color references that the owner thinks are subtle but the data makes obvious. Ginger, Rusty, Coco, Smokey, Shadow — every popular color name has a breed concentration in the matching shade. Penny is one of the cleanest cases. The name does almost nothing on black or white dogs in our dataset, and concentrates sharply on copper, chestnut, and red coats. Owners aren't being literary about it. They're describing what they see.
What's worth noting is that Penny also performs well on tabby cats with orange undertones, especially American Shorthairs. The cat side of the data isn't usually this color-matched — cat owners typically reach for celestial or flower names — but Penny is a rare exception that crosses the species line on a purely visual basis.
The Big Bang Theory effect, in dogs
The character Penny on The Big Bang Theory (2007-2019) gave the name a generation of warm, slightly clumsy, friendly cultural reinforcement. The show's twelve-year run overlapped exactly with the window when Penny climbed in pet adoption registries. The name was already on the rise before the show — it had been climbing on babies since the early 2000s — but the show normalized it for adult speakers in a way that's hard to engineer otherwise. Owners reaching for Penny in 2025 are not consciously thinking about the sitcom, but the warmth the show baked into the name is part of why it lands.
Penny on the human side has the same arc
The baby version of Penny climbed steadily through the 2010s and now sits in the SSA top 200 for girls. The pet version climbed in parallel, which is the textbook reinforcing pattern — both populations responding to the same cultural softening simultaneously. Compare this to a name like Luna, where the pet trajectory leads the baby trajectory by a few years. Penny is the rare case where the two move together, which suggests the name's appeal is primarily phonetic and semantic rather than culturally borrowed. The baby Penny page has the SSA detail.