Just like smartphones, any tablet wishing to become a Best Buy has to deliver when it comes to battery life. So to separate the best from rest, every tablet Which? tests is tested in lab conditions to see how long it lasts when browsing the web on wi-fi and watching videos.
To ensure our tests are fair, we set the screen brightness to 200 nits (measured using a light meter) before performing each task, so every tablet has to perform in the same conditions. For more information read our post on how we test tablets.
But which tablet has the best battery life?
Tablet battery life compared
As the size of the screen can make such an impact on battery life we’ve divided the tablets into two groups, those with a screen size of 7.9-inches and smaller, and those 9.4-inches and larger.
The best 10-inch tablet battery life
Apple wins this category by quite a margin. The Apple iPad with Retina display not only beats the competition comfortably, it surpasses the Apple iPad 2 by almost 4 hours. The iPad 2 still manages around an hour longer than the next nearest challenger the Sony Xperia S which managed close to nine hours and two minutes longer than the Samsung Galaxy Tab 2 10.1, which lasted 532 minutes.
Microsoft’s Surface RT tablet managed to record a respectable 501 minutes (over eight and a half hours), around half an hour longer than Google’s new Nexus 10 tablet which lasted half an hour more than the average result for all 16 10-inch tablets we have tested.
It wasn’t such great news for the Asus Eee Pad Transformer Prime, which only managed 355 minutes (five and a half hours) as a pure tablet. With its keyboard dock, which has an additional battery built-in, it lasts 661 minutes (11 hours). While this would put it second overall in the graphic above, with the dock it weighs a rather hefty 1.1kg – nearly double similar sized tablets.
The best 7-inch tablet battery life
When it comes to 7-inch tablets, Apple is still ahead of the game with the new Apple iPad Mini managing over 13 hours of web browsing and more than 3 hours more than the next best challenger, the Amazon Kindle Fire HD. The Google Nexus 7 from Asus does well with a respectable 550 minutes (nine hours and 10 minutes) of web browsing.
Unfortunately, the Amazon Kindle Fire can’t quite match the performance of its bigger brother and only recorded 437 minutes (over 7 hours), half an hour less than the average score of all 10 7-inch tablets we have tested. The Samsung Galaxy Tab 2 7.0 also disappointed, only managing 425 minutes (slightly more than seven hours).
We perform similar tests on smartphones – see which smartphone has the best battery life for the results of our smartphone testing.
How Which? tests tablet battery life
Each time we test a tablet we check the battery life for web browsing over wi-fi, over 3G (if relevant) and for video playback. To keep the tests fair we set the screen brightness to 200 nits (a reasonable daytime brightness level) using a light meter to ensure no tablet has an unfair advantage by using a low default brightness setting. We also test how long the battery takes to fully recharge.
The full results can be found in our tablets reviews where we also reveal how each product performed in our tests for factors such as ease of use and the quality of features such as the touchscreen and the camera – if it has one.
- How we test tablets – find out what happens in our labs
- Best Buy tablets - find out which tablets Which? recommends
- Tablet buyers guide - advice on choosing the right model for you