Key takeaways:
- Most cordless vacuums with strong suction power often have shorter battery life. But with a few notable exceptions from manufacturers like Dreame, Shark and Levoit.
- Our lab data reveals you don’t need to spend a lot of money to get a cordless vacuum with high-performing suction and a long battery life. We found two top performers for less than $500 from Shark and Levoit.
- Better battery life doesn’t always correlate with a higher price or a heavier vacuum.
- Most cordless vacuum manufacturers claim battery life specs of 60 minutes or more. Through our lab testing of over 100 vacuums, we’ve found only a handful live up to that claim.
The most expensive vacuum cleaner is sure to have the best battery and suction, right? As CNET’s vacuum reviewer, I wanted to debunk this common perception, with help from my partner in crime, CNET lab engineer Schylar Breitenstein.
This is CNET’s secret weapon: A state-of-the-art testing laboratory, where our in-house engineers conduct rigorous testing procedures on hundreds of home technologies like cordless vacuums. While Breitenstein rigorously tested 100 cordless stick vacuum cleaners, I dug into the lab test data to find which ones hold true to their specs and which do not.
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Our exclusive lab data might shock you as it highlighted a few hard truths for the vacuum industry. But we also found an “unprecedented” battery life winner and a handful of strong suction performers, too.
Battery life vs. price: Expensive doesn’t equal better
I went into the data expecting there to be a decent correlation between battery life and price. After all, you’d expect the more costly cordless vacuums to offer the best performance and part of what makes up performance is a longer battery life. Surprisingly, our lab data revealed that this is not the case, in fact, there’s very little correlation. It’s true, we found the cheapest cordless vacuums (under $300) tend to average around 20 to 30 minutes of battery life. But we didn’t find that the more expensive vacuums gave you more than the average battery life.
Figure 1: The y-axis shows the retail price of the cordless vacuums we tested, and the x-axis showcases cleaning time in minutes, which is representative of battery life. We divided this graph into four quadrants, each representing where the average cleaning time lands based on our lab testing (48 minutes) and the average retail price of $544.45.
If a longer battery life meant more expensive, you’d see more vacuums live in that upper right quadrant of Figure 1 above. Instead, the pattern that emerged from our lab testing shows that the average battery life of 50 to 60 minutes is when we see the real break in performance. You can actually draw a line around 55 minutes to separate the two clusters of vacuums, with most of the ones that earn a spot in our top 10 lasting at least 60 minutes.
“The most consistent values in this round of stick vacuum testing regarding price and runtime were $200 to $550 and 30 to 50 minutes of runtime,” said Breitenstein. “There are, of course, outliers that perform significantly better and significantly worse. After analyzing the data, stick vacuums that cost around $500 have the best and longest runtimes in this round of testing.”
The biggest takeaway is that our lab data proves you can find a top-performing vacuum with a long battery life at a middle-of-the-road price with the Dreame Z30, Shark Stratos and Levoit LVAC-300 all ticking this box.
The best and the worst cordless vacuums for battery life
As seen in Figure 1, two vacuums stand out: the Dreame Z30 (lower right quadrant) and the LG CordZero A949 Kompressor (upper left quadrant). But they stand out for opposite reasons.
The Dreame Z30 tested battery life is a significant outlier, surpassing the second-best performer by 30 minutes. At 110 cleaning minutes, the Dreame Z30 is the single longest-running cordless vacuum we’ve tested. It also has a fairly reasonable price, at $500, putting it in the middle of the pack in affordability while offering outstanding overall performance.
Breitenstein says the battery life performance on the Dreame Z30 is unprecedented compared to the rest of the pack. “The only other stick vacuum that can slightly compare is the LeVoit LVAC 300 at 75 minutes and the Shark Stratos at 80 minutes.”
On the other side of the testing spectrum, the LG CordZero A949. It has the single worst cleaning battery life we’ve measured at just 10.5 minutes and one of the highest prices at $1,000 without any sales. However, its suction performance is one of the best, which is why it earned a top spot on our best vacuums list months ago. It has since been displaced by newer arrivals, including the Shark Stratos, LVAC-300 and the Dyson V15 Detect — both better at suction and much cheaper in cost.
Excluding these two outliers, most of the other cordless vacuums we’ve tested fall between 35 to 50 minutes cleaning battery life before the battery dies.
Battery life vs. suction performance: Strong correlation
My theory was that the cordless vacuums with the higher sand pickup scores would have a lower cleaning time because they used more power to achieve better suction.
Figure 2: The y-axis shows the retail price of the sand pickup percentage of the cordless vacuums we tested, and the x-axis showcases cleaning time in minutes, which is representative of battery life. We divided this graph into four quadrants, each representing where the average sand pickup average (71.04%) and the average cleaning time (48 minutes) lands.
This is exactly what we found, with a couple of outliers we’ll discuss later. Generally, the vacuums with the highest suction performance, measured by overall sand pickup average, tended to drain the battery faster. The top left quadrant of Figure 2 above, shows a sizable number of high-performing cordless vacuums like the Eureka ReactiSense 440 (33 minutes), LG CordZero A949 (10.5 minutes), having average or even poor battery life.
“The higher suction the vacuum uses, the shorter the battery life is going to be because the motor is working harder,” said Breitenstein. “That’s why the Eco mode, Med/Standard mode and the Turbo/Max mode have varying results in battery life.”
That makes our handful of positive outliers more notable. In the upper right quadrant, the Dreame Z30, with its 110-minute battery life, scored a strong, though not spectacular, sand pickup average of 81.78%. It’s also joined in the top right quadrant by the Shark Stratos (95%), Levoit LVAC-300 (90%) and Shark Vertex (85%).
The worst result belonged to the Narwal S10 Pro, which took 32 minutes to clean and had a notably lower score of 48% in the bottom left quadrant.
It’s the only cordless vacuum that scored below 70% in our entire testing, though as Breitenstein points out, “The Narwal S10 Pro is a hybrid wet/dry vacuum. It’s a bit harder to test the sand pickup for those because when it senses hardwood, it wants to use the mopping functionality. That’s why they usually test lower percentage in pickup tests.”
Honorable mention also goes to the aforementioned Eureka ReactiSense 440, which has a modest 33-minute cleaning time, but the highest average sand pickup score of any cordless vacuum we’ve tested, with a 96% average. The Eureka is particularly unusual, according to Breitenstein, because it has a larger 25.9-volt battery compared with the Shark Stratos 25.2-volt battery. However, the Stratos still outperformed the ReactiSense in our battery life tests.
Battery life vs weight: Pounds don’t seem to matter
Battery life and weight is another relationship where I expected to see a stronger correlation. Generally speaking, you’d expect the heavier cordless vacuums to have a bigger battery, which should in turn give it a better cleaning time. This was not the case.
Figure 3: The y-axis shows the weight of the cordless vacuums we’ve tested and the x-axis showcases cleaning time in minutes, which is representative of battery life. We divided this graph into four quadrants, each representing where the average cleaning time lands (48 minutes) and the average weight of 7.71 pounds.
I was surprised by the results because the outcome and relationship I expected were reversed. Seen in the upper left quadrant of Figure 3, our lab data revealed that most heavier vacuums (7-plus lbs) like the Roborock F25 Ace Combo have a much shorter cleaning time (though it’s worth noting that the F25 Ace Combo is a wet-dry vacuum, so it has more components involved than a standard stick vac, even if it does break down into a stick form).
In the bottom right quadrant, the Dreame Z30 was again our standout. Its 110-minute cleaning time is powered by a cordless stick vacuum that weighs just 4.85 pounds.
“Batteries are not all created equal,” said Allen Rathey, Director at Indoor Health Council, an agency that educates professional cleaners to promote public health and healthy indoor environments.
“The newest ones are lithium ion and lithium polymer types, and their performance can vary widely based on the system in which they are used. Lithium ion batteries have great “energy density” so often can be relatively light but deliver significant power.”
Buying advice based on CNET lab data
The biggest takeaway from this analysis is that the best battery-operated stick vacuums aren’t the most expensive ones. You can buy a cordless vacuum with an above-average battery life and above-average suction performance for an average price.
Based on our lab data, the four best cordless vacuums for battery life that cost around $500 or less are:
Many companies claim lengthy cleaning times, often as much as 60 or 70 minutes. However, in our testing, we’ve found that’s not always true. In fact, just the opposite, only a handful of cordless vacuums last longer than 60 minutes. That’s what makes CNET lab testing so valuable. We can validate claims through our brand-agnostic testing.
Based on our lab data, the four best cordless vacuums for suction performance for approximately $500 partially match up with our previous list:
The two overlaps are notable in both our lists: the Shark Stratos and Levoit LVAC-300 offer the best combination of battery life and suction performance without other compromises. This isn’t surprising since both vacuums appear on CNET’s best cordless vacuums page, which takes a holistic approach to scoring vacuums. When ranking vacuums on our best list, we don’t just look at suction performance and battery life. We also take into account features, price and ease of use.
When shopping for a cordless vacuum, pay close attention to these specs
If you’re standing in a store or browsing online and trying to decide what cordless vacuum to buy, we’ve narrowed down these key specifications to look for.
- Air watts/suction power: Usually a number between 100 to 400, the higher the number, the better the vacuum’s suction strength and ability to pick up debris. “The Dreame Z30 has 310 air watts and the LG Cord Zero has 265 watts,” said Breitenstein. “Not a big margin in air watts, but the difference in battery life is profound.”
- Weight, measured in pounds, is another factor to check, since that determines how easy a vacuum is to maneuver. Lighter cordless vacuums are usually between 4 and 8 pounds (counting the stick/body, main brush head and battery).
- Battery life: Some manufacturers may give you a measure of battery capacity, measured in milliamp hours (mAh), with a higher number meaning a bigger battery and presumably a longer cleaning time. But we’ve found that doesn’t always translate well into real-life usage, which is why our spec-validation during lab testing is so important.
- Special features: Performance is important, but is just one part of what makes a vacuum effective, Ben Sawyer, senior manager of product development at Shark told us in an email. Features like anti-hair wrap technology help ensure hair reaches the dust cup instead of clogging the brush roll, he said.
Expert advice and cleaning tips
During this analysis, I reached out to industry experts and learned one easy tip we can all use on any vacuum right now to help boost its suction performance. Taylor Riley, partner and co-founder of AMR US Commercial Cleaning of Maryland, has years of residential and commercial cleaning experience. Riley says if you empty your dustbin more often, you’ll see an increased suction performance and a longer battery life.
“We’ve found that a clean, empty bin and a fresh battery is the closest you’ll get to like-new performance every time,” said Riley. “In the field, that drop in performance shows up as staff making extra passes over the same area, batteries draining faster and fine dust not getting picked up. The fix is usually as simple as emptying the bin and checking the filter.”
For most consumers, a vacuum’s battery life shouldn’t be the only feature they look for. Rathey says to judge each vacuum based on the features that help solve your home cleaning needs. Soil removal is just one factor to consider, he said. “Usability, sound levels, impact on indoor air quality, ease of maintenance, cost of filters, carpet or surface wear/impact and other factors,” said Rathey.
CNET agrees with this advice. For example, if you don’t have any carpet in your home, you may not need a vacuum designed to suction debris from carpet material. But if you have carpet and pets, you want to look at vacuums with a strong suction and battery life.
Breitenstein notes that it’s important for consumers to pay attention to floor type when choosing a vacuum. “Data analysis on hardwood pickup tests show that most vacuums perform well on this test because it’s a flat surface and requires less suction to pick up debris from hardwood,” said Breitenstein. “Midpile carpet is a true test for a vacuum because the sand easily gets lodged into the dense carpet fibers. If a stick vacuum can produce decent results for this test, it’s most likely suitable for all floor types.”
Evaluating each vacuum as a whole product versus a feature is how we choose which are the best and the worst cordless vacuums. To see which cordless vacuums we graded as the best, see our best cordless vacuums, our best cheap vacuums, our best vacuums for carpet and best for hard floors. We’ve also tested the best vacuums for pet hair and looked at brand-specific comparisons, like the best Dyson and best Shark vacuums.
How we test cordless vacuums
The first thing to understand is how we test battery life on cordless vacuums. First, we make sure it’s fully charged. Then, we run the cordless vacuum on medium suction (no Max or Eco mode) until it’s fully drained and note the time. We do this three times and then take the average of these scores to get our result.
Battery life vs. retail price
To analyze this data, I took the list price (the full retail price) of the cordless vacuum, ignoring any deals, discounts or coupons. I also rounded up to the nearest dollar. It’s also worth noting that some of the older cordless vacuums we’ve tested are either out of stock or have had significant permanent price cuts since they were first released, so the comparison may not be fully relevant, which is why older vacuums have been excluded even if they’re still available.
Battery life vs. suction performance
The relationship between battery life and suction performance was the most complicated one to figure out. I took the average sand pickup scores for each vacuum we tested and compared them against the cleaning time. I excluded any vacuum for which we didn’t have complete data in terms of cleaning time or suction.
Battery life vs. weight
For weight, I limited the weight to the cordless vacuum unit itself, not including any docks or accessories beyond the primary brush attachment and battery. I also want to call out the Eufy E20, because it was a unique combination of cordless vacuum and robot vacuum. The main vacuum unit normally sits docked in the robot. For this, I only took the weight of the cordless vacuum component, not the robot.
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