It’s no big secret that Google’s Chrome browser is a bit of a battery hog. The native browsers on both Windows and macOS (Edge and Safari) are widely reported to outlast Google’s offering. In its latest campaign, Microsoft is quantifying this difference: in a test that cycles through some common sites including Facebook, YouTube, Wikipedia, and Amazon, Microsoft’s latest browser lasted 7 hours, 22 minutes on a Surface Book system. Chrome lasted just 4 hours, 19 minutes.

Between these extremes were Firefox, at 5 hours, 9 minutes, and Opera in battery-saving mode, at 6 hours 18 minutes.

Microsoft has gone a step beyond just measuring how long each system runs by measuring the power draw of the Wi-Fi, CPU, and GPU during its test workload. A task that drew 2.1W in Edge pulled 2.8W in Chrome, 3.1W in Opera, and 3.2W in Firefox. This lower draw translates to the longer battery life.