A Which? investigation has found that some brands could be seriously overestimating the battery life users can expect from their laptop, with five out of six falling short of their battery life claims.
When compared against Which? test data, HP was the worst offender, with a brand average of 37% below claimed battery life for its laptops. The only brand that exceeded its claims was Apple – it actually managed 21% more battery life as a brand average.
Battery life is a fundamental part of Which? in-depth laptop reviews, in which we reveal how every model we test fares against the claims made by the manufacturer.
To see which laptops tick all the most important boxes, browse our Best Buy laptops.
Which laptop brands performed best for battery life?
To find out which brands came closest to achieving the battery life they claim, we collated data from two years of testing.
This data was used to create an average battery life for each brand, which was then compared with an average based on the combined claimed battery life.
As you can see from the table, HP was the worst performer. On average, Which? tests showed that its laptops underperformed by 37%, compared with the official claim. Dell wasn’t far behind, undercutting its laptop’s claims by a third (33%) on average.
Lenovo, Asus and Acer were closer, with shortfalls ranging between 14% and 17%.
The only brand that exceeded its battery life claims on average was Apple. The MacBooks we tested managed to average 21% more battery life.
Best and worst laptops for battery life claims
When it comes to individual models, we found that the best over-performer was not from Apple but Asus. Despite a brand average under performance of 14%, Asus quoted a battery life of just four hours for the Asus K570UD, released in May this year. We were pleasantly surprised to see that in our testing it was closer to eight.
HP had the worst brand average and also the worst individual performer in the battery claims stakes – its HP Spectre x360 made the bold claim of lasting sixteen hours, which would comfortably make it one of the longest lasting laptops we’ve tested. However, in our tests, we achieved just seven hours for video playback, and around six hours for web browsing.
How Which? assessed battery life claims
To find out how claims compared with reality, Which? collated data from its in-depth lab tests and compared it with the battery life claimed by the manufacturer.
134 laptops tested over the past two years were assessed, with a minimum of four laptops required for a brand to be included.
Results were combined to produce brand averages. Individual makes and models do differ, and manufacturers say they are approximate, but a clear contrast was still found between different brands.
How we test laptop battery life
We put laptop batteries through their paces in tests designed to simulate real-world usage. We don’t simply trust battery capacity claims: we actually drain the whole battery from full to empty with various tasks, several times over, without allowing the laptop to go into hibernation or sleep mode.
Out tests include watching films until the battery finally shuts down, and continually browsing websites over wi-fi. Each laptop we judge goes through our battery tests at least two times – we run a third test if results differ by greater than 10%, in order to establish a consistent result. We believe that these tests are representative of real-world use. Find out more in our guide to how we test laptops.
Poor battery life is still better than a battery that doesn’t work at all – read our guide to the most reliable laptop brands to see which ones stand the test of time.