Melting down marketing lies: Here’s how long your new laptop battery will really last


Battery life is arguably becoming a laptop’s most important metric. Processor speed is confusing – different architectures have different performance at different clock speeds. Discrete graphics is even worse. But the battery? More is better! Everyone knows that. And manufacturers have latched on to it as an important marketing tool.

This has led to amazing claims. Six, seven, eight hours or more – some modern laptops pose with endurance numbers rivaling tablets. There’s just one problem. No one checks to make sure advertising and reality match. Manufacturers can claim anything they’d like.

We’re going to take manufacturer claims to task by examining 10 recently released laptops and comparing their claimed battery endurance with the results we received during our reviews. Let’s see if these laptops can back up their boasts.

The Contenders

We wanted to have a well-rounded list of laptops for this comparison, so we’ve picked ten recently reviewed models. Some are Ultrabooks, some are desktop replacements, and some are luxury portables. Here’s the list of competitors and the battery life listed by the manufacturer on its website. Not every laptop we’ve reviewed is marketed alongside a battery life number, so we’ve picked laptops that claim a definite number. The text below is quoted from manufacturer marketing or spec sheets.

If we average all of these numbers we come to a total average battery life of 7.3 hours (rounding up slightly). That’s quite robust. Many of these laptops are portable because manufacturers usually send us high-end models for review rather than stripped-down desktop replacements, but even so, seven hours is excellent.

Now let’s see if these claims are met.

Real battery life

For the purposes of this comparison we are going to be using the numbers generated by our Battery Eater Reader’s Test benchmark. This is not a strenuous workload. It opens a document and scrolls through it endlessly. We leave Wi-Fi on and display brightness at 70 percent. We also engage the most aggressive power-saving mode available. These conditions should result in solid battery life results.

In the table below we’ve compiled our results and the difference, both for each laptop and for all laptops as a whole. Let’s take a look.

Digital Trends battery life benchmarks

What we find most interesting about these results is how well they break down by manufacturer. The Asus laptops are off by exactly 10%. The HP laptops are off by 16 percent and 15 percent. The Sony laptops are off by exactly 15 percent. Only Toshiba and Lenovo show significant variance, but both are consistent in the direction of their results – the Toshiba laptops underperformed and the Lenovo laptops beat their estimates.

Lenovo’s IdeaPad U400 is the real surprise thanks to an insanely low manufacturer claim of four hours. We applaud Lenovo for apparently being more realistic about real-world results, but at the same time, Lenovo’s laptops offered shorter run times than the competition.

Interpreting the results

The overall variance is negative 11 percent, but if we exclude Lenovo, the difference increases to negative 14 percent.

Does this mean that you should expect at least 14 percent less than what is claimed? Yes, it does. Though these 10 laptops are obviously only a small portion of the market, in our experience it is rare for any laptop to meet its claimed maximum life under any conditions that involve active use of the laptop.

Even expecting 14 percent less than what is claimed may be hopeful. The benchmark reference in this article is the least demanding of the two we use. Placing a heavy load on the processor is going to eat through the battery even more quickly. Playing a game, for example, can cut battery life below 50 percent of what is claimed.

Manufacturers account for this by using the words “up to” in their advertising. With that said, some manufactures walk a finer line than others. ASUS claims the UX31 can achieve 7 hours or more on the specifications page of its website. Toshiba claims that Z835 offers up to eight hours of “non-stop browsing, emailing, doing and enjoying.” These claims are simply incorrect.

Though it’s possible that a laptop will meet or exceed its claim, you shouldn’t expect it. Instead, you should expect a laptop to come in below its maximum by at least 14 percent and – more realistically – around 25 percent.

A silver lining

All of this sounds a bit doom-and-gloom, so let’s end on a high note. While we do find that laptops fail to meet their quoted endurance in our battery life benchmarks, there has been an upward trend in real-world battery life.

Five years ago you’d be lucky to achieve three hours with a basic desktop replacement, but the worst battery life we recorded among the systems in this comparison was a tad over five hours. The average buy should find this to be more than adequate. Even if claims are not being met, real-world battery results do not fail to impress.


In the age of Alexa and Siri, Cortana’s halo has grown dim

In a sea of voice assistants, Cortana has become almost irrelevant. The nearly five-year-old voice assistant is seeing little love from consumers, and here’s why it is dead.

Take $250 off the HP Spectre x360 laptop with this Presidents’ Day sale

If you're hoping for something more powerful that will last more than a few months, you'll probably need to invest $1,000 or more. Unless, of course, you take advantage of the Presidents' Sale on the HP Spectre x360 13t.

From Chromebooks to MacBooks, here are the best laptop deals for February 2019

Whether you need a new laptop for school or work or you're just doing some post-holiday shopping, we've got you covered: These are the best laptop deals going right now, from discounted MacBooks to on-the-go gaming PCs.

In 2019, laptops are better than ever. Here are the best of the best

The best laptop should be one that checks all the boxes: Great battery life, beautiful design, and top-notch performance. The laptops we've chosen for our best laptops you can buy do all that — and throw in some extra features while…
Product Review

Asus Zephyrus S is a laptop for gamers. Everyone else need not apply

RTX graphics have finally made it to gaming laptops, and the first we've tested is the new Zephyrus S. Now with a 17-inch display and those new graphics inside, the Zephyrus' unique design boasts some additional power.

Wi-Fi helps connect all of our devices at high-speed, but what exactly is it?

What is Wi-Fi? It's a technology we all use everyday to connect all of our portable devices, but understanding how it works and how far it's come from its humble beginnings is another thing entirely.
Emerging Tech

Awesome Tech You Can’t Buy Yet: Grow veggies indoors and shower more efficiently

Check out our roundup of the best new crowdfunding projects and product announcements that hit the web this week. You may not be able to buy this stuff yet, but it sure is fun to gawk!

Are you one of the billions who have watched these super-popular YouTube videos?

Viral videos can quickly garner millions upon millions of views, but even they fall well behind the view counts on the most watched YouTube videos ever. Those have been watched billions of times.

Windows updates shouldn't cause problems, but if they do, here's how to fix them

Windows update not working? It's a more common problem than you might think. Fortunately, there are a few steps you can take to troubleshoot it and in this guide we'll break them down for you step by step.

Speed up your system by tweaking the startup application in Windows and MacOS

Bothered by programs that automatically start when you boot your computer, or want to add a new one to the list? Here's how to change your startup programs in Windows 7, 8, and 10, along with Apple's MacOS.

Marriott asking guests for data to see if they were victims of the Starwood hack

Marriott has created an online form to help you find out if your data was stolen in the massive Starwood hack that came to light toward the end of 2018. But take note, it requires you to submit a bunch of personal details.

Apple may go big with a redesigned 16-inch MacBook Pro, 31.6-inch 6K display

In a research note, well-respected Apple analyst Ming-Chi Kuo writes that there are indications the company could be releasing a 16-inch MacBook Pro, as well as a 31.6-inch 6K display in 2019.

Accidental Amazon listings provides peek at cost of GTX 1660 Ti PCs

An accidental listing on Amazon provided a peek at the final cost of some of the new Windows 10 desktops with the GeForce GTX 1660 Ti on board, with prices possibly in the $1,200 range.

The best Presidents’ Day sales 2019: Amazon, Walmart, Dell, and more

Presidents' Day sales are a great chance to score electronics, clothing, home and office stuff, and other goodies at a discount. We’ve smoked out a large handful of the best of these Presidents' Day deals, from tech to bedding, to help…