You probably already know that the battery life rating for laptops, tablets and phones don't often match reality. Laptop Magazine explains why and offers a sound rule of thumb for buying your next laptop. Photo remixed from an original by IntelFreePress.
Laptop Mag's battery tests (continuous web surfing over Wi-Fi at 100 nits of brightness) reveal the discrepancy between manufacturer's maximum battery life and tested results.
One reason for the discrepancy is PC manufacturers use different tests and criteria (sometimes not as demanding as the ones reviewers or consumers use) to estimate battery life.
It just sucks when your computer shuts down several hours before you expected it to, so take their advice:
As a consumer, you can vote for a better laptop market with your wallet. Buy laptops that, on objective tests, get at least 50 per cent more battery life than you think you'll need in a day. If you think you might really use your laptop away from a desk for 5 hours a day, get something with 8 or 10 hours of battery life as measured by us, not by marketers. You may end up with a slightly thicker laptop, but you'll be a lot happier not being shackled to the wall.
For more battery life tests and explanations, check out the link below.
The Big Short: Laptop Makers Exaggerating Battery Life [Laptop Magazine]