Starbucks coffee is known for being costly, but your morning dose of caffeine also comes with the fastest free public Wi-Fi.

The Wi-Fi at Starbucks ranks the fastest download speed at 9.01 megabits per second (Mbps). Its Internet speed is twice as fast as McDonald's, which is about 4 Mbps. 

According to the U.S. Wi-Fi Report from Open Signal, customers get more bang for their Starbucks with an Internet speed that is faster than the best 4G networks. Both AT&T and Verizon Internet service providers offer 4G speeds at only 6.52 Mbps.

The coffee giant announced last July that 7,000 locations would be dropping AT&T and replacing the service provider with Google.

"Every day, our customers rely on the free Wi-Fi at Starbucks to study, work, connect with friends or just relax," Adam Brotman, chief digital officer at Starbucks said. "We want to make sure that they can access the web effortlessly and quickly, no matter what they're doing, or what device they are using.

Other retailers who offer free Wi-Fi include Best Buy with a download speed of 3.9 Mbps. Panera Bread, another popular public spot to access Internet, only offers 1 Mbps.

If you want to avoid spending high costs when on vacation, lounging in Starbucks will save you money when compared to hotel W-Fi costs. The Hilton has the fastest Internet speed with 8.47 Mbps, but is a $100 per night.

So ordering that caramel macchiato for $4 to stay seems worth every cent.