According to Google, Pixel smartphones previously used rigid assumptions to calculate how much battery life was remaining at any given time. "If you’ve used about 10% per hour over the past few hours, we would guess you will keep using 10% per hour," wrote Michelle. "As you might expect, this wasn’t always very accurate."
Google has now switched to an on-device model that will continually monitor your battery life over time. Among other variables, Google will now compare your battery usage on similar days and times to help better predict your estimated battery life remaining.
For example, if you tend to watch YouTube videos on your commute to and from work, over time, your Pixel will take this battery draining activity into account when providing battery life estimates.
It's easy to see these new predictions that Google has put in place by navigating to the Settings menu and then heading to the Battery section. From there, you will find your own personalized battery estimates, which will provide you with a readout of the percentage of battery you have remaining and an estimated of how many hours and minutes you have left until you'll be staring at dead phone.
You can also click on the blue battery icon to see the estimates plotted out graphically over time based on your usage.
According to Android Police, this functionality was already implemented on the Pixel 2 and Pixel 2 XL, but has now been fully adapted by the first-generation Pixel and Pixel XL smartphones.