Tobi ranks at #564 with 222 entries, registered male. It reads as a friendly short-form of Tobias or Toby, and the -i ending instead of -y signals either a German naming influence or a deliberate stylistic choice to soften the name a half-step. Either reading lands the same place phonetically: TOH-bee, two syllables, easy recall.
The German connection
Tobi is the standard German diminutive of Tobias, where the spelling Toby is rare. A meaningful slice of American Tobi pets come from German-American households or from owners who picked up the spelling from German football, music, or anime fandom. The Naruto character Tobi (a major Akatsuki figure) is a separate and significant pop-culture anchor, particularly for owners under 35.
Sound and breed lean
The two-syllable, front-stressed shape with a soft B and the long-E ending sits in the warm-and-friendly register alongside Cody, Bobby, and Sammy. The name lands on medium-sized friendly breeds — Beagles, Cocker Spaniels, mixed-breed shelter dogs, and the occasional Dachshund. It works less well on intimidating breeds; the softness of the ending undercuts a guard-dog register.
Tobi versus Toby
The Toby pet page sits much higher on the chart and represents the dominant English spelling. Tobi owners are usually choosing the alternate spelling deliberately, either for the German register, the anime anchor, or simply to differentiate from the dozens of Tobys at the dog park.