Nation The world’s oldest living dog, a chihuahua named TobyKeith, breaks Guinness World record April 20, 2022 Asha C. Gilbert, USA TODAY Comments Off on The world’s oldest living dog, a chihuahua named TobyKeith, breaks Guinness World record A Florida chihuahua named TobyKeith is the world's oldest living dog at 21 years old, Guinness World Records confirmed.