The Red Bull driver is likely to secure his fourth successive championship on Sunday at the Indian Grand Prix, and Ricciardo believes that the German has remained at the top of the standings because of his desire to remain as the number one man in the sport.
The 24-year-old told Sky Sports News: "I think he is a very driven kid. A lot of people say that he has the best car, but even with the best car, you have still go to do it.
"I'm sure in the past that people with the best car still haven't won the title.
"It's easy to judge the book by its cover, but Mark Webber is no slouch and he has won four in a row against him."
Ricciardo will leave Toro Rosso at the end of the season to become Vettel's new teammate at Red Bull.