Gas vs. Battery String Trimmer: Which Is Better?

In our testing, battery and gas string trimmers earn similar scores. But battery string trimmers have a narrow edge over gas-powered ones because the top-rated battery models outperform the best gas models. Still, in almost every case, it depends on your preferences and use case. It’s easy to find a gas string trimmer that matches or beats the performance of battery models.

Battery string trimmers, like all battery outdoor tools, perform better now than they ever have in the past. They’re also better for the planet and better for your ears, and over time they’re probably better for your wallet, too, when you factor in gas string trimmers’ lifetime cost of gas and, in some cases, oil.

Battery-powered models also have an inherent advantage gas doesn’t: the interchangeability of the battery. Brands that make battery string trimmers know you’ll likely want to use that same battery in another tool, such as a lawn mower or leaf blower. And in most cases, you can. If you buy a battery outdoor tool, make sure to buy into the platform, not just the one tool—check to find out whether the brand you buy also offers other outdoor tools with high scores in our ratings. The advantage here is twofold. If you amass enough tools from the same brand over time, you can buy some of them without batteries and simply use the same batteries for multiple tools and keep one charging at all times. And with a charged battery on hand, you’ll never run out of juice.

As it stands, a gas string trimmer’s single biggest advantage is that you can keep cutting as long as you need, provided you keep adding gas. But a backup battery solves the same problem for a battery trimmer. The cutting times you can expect from a battery string trimmer range from a lackluster 15 minutes up to 45 minutes on a single charge. So if you’re buying only a battery string trimmer to start, make sure to choose a model with a run time long enough to tackle your entire yard on a single charge. 

Gas makes sense if you’re not ready to buy into a battery tool platform and you have a big yard you want to knock out in a single session, without waiting for a battery to charge. 

Use our string trimmer ratings, along with the top-performing models below, to find the tool that’s best for you.

We use each trimmer to tackle typical yard weeds and high grass as well as dense brush, noting and timing how long each model takes to clear a defined path. We also test each model’s edging and trimming, its ability to create a neat straight line along a walkway vertically and horizontally. And we look at how easy each trimmer is to hold, maneuver, and operate, noting how difficult it is to start up or feed extra line through the cutting head.

We test gas and battery models with curved and straight shafts. If you’ve never used a string trimmer, try handling curved-shaft and straight-shaft models in a home center or hardware store to see which type feels better. In general, tall users may favor straight-shaft models because they have a longer reach. Shorter users may prefer curved-shaft models because they can be a bit easier to control.

Our engineers took years’ worth of string trimmer testing data to build a tool that allows us to compare scores from dozens of models, both gas- and battery-powered. We compare average scores for gas and battery string trimmers in the following tests: trimming, edging, tall grass, handling, ease of use, and noise. We also look at run times for every battery model and across battery models in general. 

Keep in mind that we compiled this information to compare models across categories. In your own yard, the only thing that matters is the performance of the specific string trimmer you choose. For that reason, we’ve included some top-rated models of each type below.

Here, we settle the score on which type of string trimmer, gas or battery, performs better overall.

Most people will probably use their string trimmer for trimming areas their lawn mower can’t reach more than for edging or clearing tall grass. 

Which is better? It’s a tie. Both earn the same average score for trimming. On average, gas and battery models earn a 4.6 (out of 5.5) in this test. We have plenty of battery string trimmers that earn perfect scores in our trimming tests, just like the best gas models. But gas models that are bad at trimming still score slightly better than battery models that are bad at trimming. So if you decide to go with a battery model, make sure you select one that gets the top score in our trimming test.

Edging lets you cut a clear line where your grass meets a patio or walkway, leaving a clean-looking divide between the two. 

Which is better? Gas. There are plenty of battery string trimmers that ace our edging test, but a few duds drag down the entire class. The vast majority of all trimmers, gas and battery, do pretty well in this test, but the worst battery model earns an abysmal score of 2.4, while the worst gas string trimmer still musters an impressive score of 4.2.

If you’ve left a swath of your yard untrimmed for some time, you’ll want a model that can plow through tall grass and weeds. This test is also where we see some of the biggest performance differences. 

Which is better? Gas, by a small margin. Gas models average a score of 4.9 and battery ones average a 4.5. Notably, almost all the gas models we’ve tested perform pretty well on this test, while the battery-powered ones are all over the map. The best gas and battery models have comparable performance, but the worst battery-powered ones really struggle—the lowest-scoring battery device earns a 0.5, while the worst gas model still manages to earn a 3.4.

Handling reflects how evenly balanced and responsive a string trimmer is. Gas models need to account for a heavier engine and gas tank, but battery-powered models need to balance the weight of lithium-ion batteries, which can be heavy.

Which is better? Battery. Battery string trimmers earn an average score of 4.3, while gas models earn a 3.9.

This test factors in starting up the trimmer, accessing controls, handle comfort, and the ease of feeding or advancing the cutting line. 

Which is better? Gas, which has an average score of 3.9, vs. battery trimmers, which have an average score of 3.8. But that may be because the gas models we’ve tested tend to be better at feeding and advancing the cutting line—the biggest problem with string trimmers. As a rule, many would argue that battery string trimmers are easier to use because they start instantly. If you want a battery trimmer for its easy starting and maintenance but you struggle with loading its cutting line, consider an aftermarket string trimmer head. These devices work with gas and battery models and are often available at home centers and hardware stores for $20 or less.

We measure noise for outdoor tools both at the ear of the user and at 50 feet—a distance chosen to see how loud the sound might be for a neighbor and whether you need hearing protection—a must for gas models.

Which is better? Battery, by a mile. Even the loudest battery string trimmer is less noisy than the quietest gas model. On average, battery string trimmers earn a score of 2.9, while gas models average an abysmal 1 (the lower the score, the worse the noise). The quietest battery models earn a perfect noise rating of 5.0. According to our testers, trimmers that earn a 4.0 or higher are safe for the ears. They would recommend that users wear hearing protection for any model that earns lower than a 4.0 for noise.