It's no secret that Toby Keith is one of country music's most savvy businessmen. He appears on the cover of the upcoming Forbes issue that lists the 100 highest-earning celebrities, and the accompanying article reveals the true size and extent of his financial holdings.

The magazine states that Keith earned $65 million in the last year -- far more than celebrity moguls like Jay-Z, Beyonce and Jennifer Lopez. The singer-songwriter has written a No. 1 hit every year for the last 20 years, and he also owns a piece of the enormous success of Taylor Swift, through his Show Dog label's partnership with her label, Big Machine.

Add to that his own Wild Shot mezcal line, a chain of I Love This Bar & Grill restaurants, a multi-million-dollar endorsement deal with Ford, merchandising, concerts and more, and Forbes estimates Keith's total career earnings at $500 million.

“He’s built this little empire, and he did it kind of quietly,” concert promoter Louis Messina observes. “Not many people have been able to pull it off as long as he has.”

The issue of Forbes featuring Keith hits newsstands July 15.