Don’t believe manufacturer claims about laptop battery life – unless it’s a MacBook

According to consumer watchdog Which’s testing, notebook manufacturers are seriously overstating their estimations of battery life, with one notable exception – Apple and its MacBooks.

A new report from the consumer watchdog pulled figures from lab tests of the battery life of some 67 laptops put through their paces since the beginning of 2016.

The report by Which found some pretty big discrepancies between the makers’ claimed battery longevity, and how long the device managed to last for in its own tests, with the biggest differences coming from HP and Dell machines.

HP laptops – of which 12 were tested – had an average claimed battery life of 9 hours 48 minutes, but in Which’s real-world testing, these portables averaged 5 hours 2 minutes. That’s not much more than half of the manufacturer’s estimation.

With Dell, across 10 laptops, the average claimed life was 9 hours 15 minutes, with Which finding it to be 5 hours 12 minutes. Toshiba’s average claimed life (for 6 machines) was 7 hours 58 minutes, with the test results showing 4 hours 45 minutes.

Some other notebook makers were a bit closer to the mark, but still adrift, with Asus having a claimed average of 10 hours 12 minutes, compared to a result of 6 hours 53 minutes (over 8 notebooks).

Also across 8 machines, Acer had an average claimed life of 7 hours 53 minutes, compared to a test result of 5 hours 59 minutes. And for Lenovo over 20 laptops, claimed life was an average of 6 hours 41 minutes, compared to 4 hours 34 minutes. So those were closer to the mark, particularly in the case of Acer – but still considerably behind manufacturer estimations.

Only Apple came out of this benchmarking with its head held high, because the three MacBooks tested had an average claimed life of 10 hours, yet managed to last longer than this, hitting 10 hours 15 minutes.

Which doesn’t mention whether one of the MacBook Pro with Touch Bar models was included here, which would have been interesting to know given the battery life complaints of recent times.

Testing times

You may, quite rightly, be wondering exactly how Which tests battery life. The watchdog explains that it performs two main tests during the evaluation of laptops, and runs them at least three times, draining the entire battery in the course of both tests.

One test involves browsing websites over Wi-Fi, and the other watching a movie until the battery gives out. However, Which doesn’t clarify considerations such as what the screen brightness is set at, or indeed in the movie test, whether that’s a streamed film from YouTube, for example, or a USB drive (presumably it’s not a movie played off a disc, as not every notebook has an optical drive). 

The watchdog says: “We believe that that these tests are representative of the real world use that a laptop would get.”

Clearly, though, whatever the exact details of the above tests, it’s still interesting to see the relative results, and it's quite an eye-opener as to how exaggerated some manufacturer claims appear to be. And indeed, how well Apple does compared to Windows notebooks.

There was also an in-depth look at a few highlights of individual results, with the likes of the Lenovo Yoga 510 falling way, way short of its claimed battery life of 5 hours – only managing 2 hours 7 minutes, in fact.

Some of the notebook makers were, of course, quick to point out that gauging battery life is a tricky matter depending on the exact usage of the laptop. As Dell told the consumer watchdog: “Every individual uses their PC differently – it’s similar to how different people driving the same car will get different gas mileage depending on how they drive.”

Incidentally, if you want to maximize the battery longevity of your laptop, check out our guide here.

Darren is a freelancer writing news and features for TechRadar (and occasionally T3) across a broad range of computing topics including CPUs, GPUs, various other hardware, VPNs, antivirus and more. He has written about tech for the best part of three decades, and writes books in his spare time (his debut novel - 'I Know What You Did Last Supper' - was published by Hachette UK in 2013).