The Best String Trimmers

• The 4 string trimmers we tested
• 1. Best overall:
  Black+Decker – LST136W
• 2. Best for heavy work:
  Ego – Power+ 1502-SF
• Other products we tested
• How we selected
• How we tested
• How to edge-trim your lawn
• Types of trimmers
• Important features to consider
• The bottom line

The Black+Decker – LST136W is a compact, lightweight but powerful trimmer that will be ideally suited to most home edging and trimming needs.

Weight is a big consideration here: we liked how easy it was to carry this trimmer around. The fact that it can be collapsed to a smaller size for storage is a great bonus. The other tools fold or come apart, but that makes for an unwieldy package.

None of the conveniences would be a worthwhile trade-off if this trimmer couldn’t keep up with the cutting tasks, but Black+Decker managed to hit a sweet spot for efficiency and power. The motor tackled thick, overgrown grass that bogged down even the big Ryobi trimmer, and it managed to cut heavy stalks (like the pictured fig-tree shoots) better, too.

If you’re dealing with household chores like trimming lawn edges and cutting weeds around flower beds, this trimmer does amazing work given how light it is.

Best Overall: Black+Decker - LST136W

This is all the trimmer most people will need in a lightweight, high-performance package. Perfect for city lawns and gardens, it also out-cuts some bigger models if you take it out to the back 40.

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Even better, there’s an easy-to-use speed dial that will vary the amount of juice the motor is using: if you’re just trimming a bit of grass or light weeds, you can turn it down and get even longer runtime from the battery. We ran all our tests with the power cranked up to full and were still satisfied with the battery capacity, but it’s nice to know that you can go for longer if you’re not pushing the performance envelope.

There are definitely jobs that this trimmer is too small for, but the motor and battery aren’t really the limiting factor. If you’re working around sharp stones or tough plants like vines, then the 0.065-inch trimming line will disappear quickly.

With unexpected line breaks, and it was sometimes frustrating having to wait for the Black+Decker’s automatic feed system to pay out more line. We even bypassed it a few times by opening up the spool and unwinding a few turns manually after losing a big chunk of string. Bigger machines with 0.080-inch line won’t last too much longer when dealing with tough material, but they are designed to quickly feed out more line after it breaks.

Probably the biggest disappointment of this machine is the length of the shaft and the difficulty of attaching a standard shoulder strap bracket. If you’re much taller than six feet, you might be annoyed by how far you need to stretch your arms to reach the ground with the optimal cutting angle.

Adding a shoulder strap helps, since your arms aren’t carrying all the weight anymore. Since the shaft of this tool is too thick for a “universal” strap bracket, we had to improvise an attachment point; it’s not pretty, but it works. If you’re shorter in stature, the adjustable-length shaft is very easy to set at exactly the right length for good posture and easy work.

Key takeaways:

• The Black+Decker – LST136W is the lightest trimmer we tested and collapses neatly for easy storage.
• The weight savings don’t cost you much in terms of cutting power, and we were impressed with how capable this 13” trimmer is in the field.
• 33 minutes of working time is close to average, but there’s a handy power dial feature to save power when you’re only doing light cutting.

If you scoff at the term “lightweight” and are looking for a battery-powered trimmer to replace a gas model, Ego’s Power+ ST1502-SF is made to fit your needs.

With a higher-voltage “Power+” battery system that pumps up the wattage available to its motor, Ego’s trimmer also uses commercial-grade 0.095-inch line that will cut heavier material better than any of the other electric trimmers we tested.

For Heavier Work: Ego - Power+ 1502-SF

For overgrown grasses and big weeds: Ego’s 15-inch trimmer is quiet and powerful. Its commercial-grade line effectively cut through thick growth better than any of the other electrics we tested.

See Price at Home Depot

The available power comes at a price: with only 36 minutes of runtime despite the massive 2.5 amp-hour battery, this machine is just barely viable for big jobs on an acreage. (This trimmer runs at a higher voltage than the others, so the battery has more cells inside.) It’s heavy enough to make your shoulders and back sore the first couple of weeks you use it. That said, this is lighter than the Ryobi 15” trimmer or a gas-powered model, and a shoulder strap is a good idea anyhow.

Fortunately, the battery charger got the same treatment as the rest of the machine, with an integrated cooling fan and beefy power supply. The charger reliably refilled the 2.5 AH battery in less than 45 minutes. That’s impressive even compared to the Greenworks charging system, which only had to refill 2.0 AH and took an hour.

We don’t really have anything bad to say about the Ego trimmer, and it was far more powerful than the Ryobi’s competing model, but we found that for city lawn work it was a bit overkill.

You can definitely do most of the jobs this trimmer will do with the Black+Decker, and our top pick has a wire guide and rotating head for easy edging jobs. The Ego’s hand grip lets you hold the trimmer sideways to do edging, but it doesn’t feel like a purpose-built solution the way our top pick does.

Key takeaways:

• The Ego – Power+ 1502-SF has a 15-inch cutting head with commercial-grade cutting string and a 36-minute runtime.
• Ego has dropped the gauntlet and puts gasoline-powered toolmakers on notice. There are still pros who don’t have the option of waiting for a battery to charge every half-hour, but for the rest of us, this is the best big trimmer to buy.

3. Greenworks – 2101602 G-MAX

Greenworks has released the 2101602 trimmer as part of their G-MAX system, and while it doesn’t make top grade, it’s a very capable machine.

The biggest hindrance to this trimmer is weight and ergonomics. While the Black+Decker tool weighs in at a very slim 6.8 pounds, Greenworks only managed 7.8, with a smaller battery, and with a drop in cutting power.

The performance of this trimmer is acceptable for most situations: the line only reaches 12-inches in diameter compared to the Black+Decker’s 13-inch, but Greenworks has two lines spinning at the same time as the big 15-inch trimmers do.

We felt that they were on fairly equal footing in terms of cutting power if you dial back the Black+Decker control wheel to 85 percent power, which roughly matches any difference in runtime, too.

If you don’t think you’ll ever want to cut anything heavier than grass, the Greenworks will save you some money and charges a bit more quickly, but we really liked the option of bumping up the power just a little bit with Black+Decker’s system.

The one case where we’d recommend this trimmer over the Black+Decker is if you’re much taller than six feet. The Greenworks trimmer’s longer reach makes it a bit easier to find a balanced handle position, and mounting a “universal” shoulder strap isn’t as tricky.

4. Ryobi – RY40220

The Ryobi line won top spot in Consumer Reports’ roundup, and The Wirecutter liked this one enough to give it runner-up pick.

The Ryobi – RY40220 trimmer gives you a ton of options. If the first thing you’re looking for is a tool system that will let you do hedge trimming, roto-tilling, and leaf blowing with a single battery and motor module, then it might be worth considering.

Sadly, Ryobi’s lawn tools aren’t compatible with their cordless shop tools. Ryobi’s 40-volt system doesn’t offer nearly the same power as the Ego 56-volt system, either, nor is it significantly cheaper.

On the whole, this trimmer was pretty disappointing. It’s loud: not nearly as loud as a two-cycle gas engine, but far louder than any of the other electric trimmers we tested. It’s also heavy, about one pound shy of a gas-powered trimmer and two pounds more than the Ego (despite that bigger battery).

In thick, tall grass or against stout weeds, the Ryobi just didn’t seem to have enough power to keep up. The worst-case scenario for this particular tool seems to be thick grass: clumps of tall quackgrass that Black+Decker’s lightweight trimmer buzzed through easily seemed to be too much for Ryobi’s motor or drive system.

On vines and thick stalks like the fig saplings pictured above, the motor would slow down enough that the cutting string started wrapping instead of cutting, and we had to move much more slowly and more deliberately to cut weeds efficiently with this trimmer.

Those tough-cutting situations are not great for any weed whackers since tough stalks and vines will also start wearing and breaking your trimmer line. We’d prefer to use up the line more quickly, though, if it means we can get through occasional patches of heavy weeds without bogging down.

Ryobi’s bump-feed system works well, with slightly more consistent re-loading than Ego’s, so it’s not a total failure as a serious tool. Without more power to cut through tough spots, though, the refinement seems a bit of a waste.

Ryobi has also faced some criticism in customer reviews over the batteries they sell. Some users are reporting that their batteries won’t charge anymore after a few months. There are some unrealistic expectations in the Home Depot customer reviews: cordless lawn tools shouldn’t be expected to run for more than 30 working minutes. Failing to charge, though, is a serious problem.

We haven’t had any problems with our Ryobi battery yet, and we didn’t see the problem mentioned in the other major reviews, but we’ll update if ours kicks the bucket.

First, we looked at reviews and customer feedback for the top-selling trimmers on the market. We also covered the top-placing trimmers from publications like Consumer Reports and the Wirecutter.

We reviewed battery-powered trimmers, because, let’s face it, two-stroke gasoline engines are noisy, smelly, and expensive. Gas trimmers earn a place on the trucks of professionals with top power and long run-times, but most homeowners will be happy with clean, quiet and simple battery power.

While we set out to test battery-powered trimmers, we also used some other tools alongside our test lineup for comparison. We included a gas-powered Stihl – FS 70 R in our tests to see how the electric trimmers compare to the industry-standard workhorse that’s already doing the heavy work for landscapers and ranchers. We also purchased and used a plug-in edge trimmer and trencher, the Black+Decker – LE750.

We picked a set of top-ranked trimmers in two size categories: trimmers with 15-inch cutting heads as well as compact 12-to-13-inch machines. We bought from brands with good reputations for warranty coverage that are available at major retailers. (In comparison, many commercial-grade brands like Stihl are only available through a dealer network.)

When selecting a trimmer from Ego, we picked the best-priced package at the time, the 1502-S. Ego’s model numbers are a composite of the trimmer model, battery size, and extra features. This kit includes a 2.5 AH battery and the 1500 trimmer with “split-shaft” folding for storage. This review has a table that explains the differences in kit accessories and features.

There’s a new model that has replaced the -S, called the -SF, with a “rapid reload” head in addition to the split shaft. Everything else about the kit is the same, so we’ve updated links in this review to point to that kit instead.

In addition to testing for lawn-duty use in the city, we sent this lineup of trimmers to an avocado orchard in southern California. The trimmers arrived at the ten-acre grove just in time to begin work cleaning up all the weeds that had sprung up after a fall fertilizer application. Our testers cut weeds ranging from mundane dandelions and crab grasses up to the imposing four-foot-tall horse thistles.

The orchard already uses a selection of gas-powered trimmers, mostly mid-size Stihl models like the FS 70 R. We’ve included direct comparisons to the Stihl where it makes sense, but as context rather than as a purchase recommendation: we believe that most home users are going to be happier with a cordless electric trimmer.

Weight

As mentioned in our section on features, none of these trimmers were supplied with a shoulder strap, but they really should be. We tested each model without a strap for a few weeks before ordering a generic strap from Amazon.

These trimmers are quite light compared to the gas-powered engines that professional landscapers are using for hours at a time, but that doesn’t mean they’re easy on your shoulders and back. If you’re only planning to do quick touch-up trimming, the Black+Decker – LST136W is not too bad without a shoulder strap; for any other purpose, get a strap.

Cutting ability

This was one of the trickier values to test for. Each of these trimmers will cut grass easily, but the upper limit of cutting capacity is harder to define.

We measured the biggest weed stalks that could be cut cleanly by each trimmer. We tried to bog down the trimmers in extra-dense grasses. We even skirmished with some materials like saplings and vines that are just too tough to cut effectively with string trimmers.

The wattage rating here is a value derived from the nominal capacity and voltage of each battery system divided by how long the trimmers run before shutting off. Between batteries with the same capacity and voltage, a shorter run-time means more wattage is being pulled by the motor.

The chart above rates each tool on a scale of five based on how effectively it cut, but note that the smaller trimmers use a thin line that disappears quickly if you’re cutting tough woody material.

There are a lot of similarities between trimmers of the same size, but each manufacturer has taken its own approach to find a balance of power, battery life, and weight.

The Ego trimmer has impressive power, ripping through all but the very toughest weeds. The other trimmers stopped cutting green leafy weeds when stalks got bigger than 0.45 inch, though the Ryobi trimmer often failed on anything bigger than 0.35 inch.

Gas trimmers probably have enough power to cut through very thick material, but the trimming line will usually start to wear away before you reach the limit of engine power.

Line advance

The different systems used to release more cutting string have their strengths and failings, but we ranked them here based on how easily and quickly we could get back to cutting at full speed after a rock or vine ate away at our trimmer string.

The automatic-feed systems are okay for general use, but for cutting in the field where string sometimes goes quickly, we preferred a system like the bump-feed that gives some control over how much line is fed out and when.

Battery tests

We timed how long each trimmer will run under the same conditions, with the motor running constantly and cutting in dense grass and weeds.

As you can see from the charts, run time tracks pretty closely with the size of the battery and the amount of power the trimmer puts into cutting. The more work the tool does spinning the trimmer line, the shorter the battery life.

We also timed how long it takes to recharge the batteries with the included chargers; this will be a more important detail for some buyers than others.

The most surprising result is the Ryobi system; the short run-time on a high-capacity battery means it’s pumping a lot of watts through its motor. The fact that this trimmer also suffered poor cutting performance suggests an inefficiency in the drive shaft system that allows changing to other tool types. (It’s certainly the noisiest trimmer, and more noise is never an indicator of an efficient electric drive system.)

As noted previously, we’re using a nominal advertised power rating for the Stihl 2-cycle engine (0.9 kilowatts) that seems accurate. It has far more power available than the battery systems, and every fill of the 11.5 oz tank will give you about 34 minutes of run-time.

While a lawnmower is basically essential to the health of your lawn, string trimmers and leaf blowers are a bit more of a luxury. You’re keeping your grass at the right length, what’s left to do?

String trimmers are great with grass and weeds in all of the locations where a mower can’t help. Does your lawn have a corner where your mower won’t fit? Mow it with a string trimmer. A patch of weeds sprouting behind your trash cans? The string trimmer will take care of those, too. Want a clean edge between your grass and driveway? A good string trimmer will make edging easy.

Unless you own a home in a desert or polar region where nothing grows, a string trimmer can probably make your yard work easier.

Because the string that’s doing the cutting is flexible, you can cut right up to a tree or planter or post and not worry about damaging anything. The string will only cut through soft fibrous material like green plants, barely leaving a mark on big trees, concrete or metal. You should still be careful not to hit young trees and flower beds, of course, but it’s much easier to safely get close than it is with a mower.

String trimmers are even more popular on acreages and farms where hillsides and rocky patches make mowing impossible. Even in dry climates where grass landscaping and mowers are scarce, string trimmers can take care of the weeds that pop up.

If you’ve got a lawn that your mower covers perfectly and you don’t mind pulling your weeds by hand, you might not need a string trimmer. If you’ve got a bigger yard, though, there are almost certainly areas a string trimmer can help.

While a lawnmower trims grass that stands up in the air, it won’t do anything about the grass that lies flat or bends over and spreads onto your walkway or driveway. A trimmer can cut those leaves in a precise line along the edge of your lawn.

Edging your lawn with a string trimmer is quick and easy. First, turn the trimmer so it cuts up and down instead of parallel to the ground. Most have a rotating shaft or a multi-position handle so you don’t have to contort your upper body while holding the trigger in this position.

Walk the trimmer head down the edge of the lawn. Many trimmers have some sort of guide or another indicator that helps you track where the cutting string will hit. The rapidly spinning string will slice through any blades of grass that cross over onto your sidewalk and leave a clean edge. Typically the guide is set so that you dig a neat, narrow trench into the dirt along the edge; if you just want to cut the grass, you’ll have to lift the trimmer a few inches and hold it steady while you walk it along the line.

For Edging and Trenching: Black+Decker - LE750

This is an edger for people who want straight, clean, well-defined edges. It won’t mow in the corners like a string trimmer, but it will cut small trenches to run wires for backyard lighting projects.

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Edgers like the Black+Decker – LE750 are built for edging and trenching only. A tool like this uses a solid metal blade rather than a flexible string, and this has a few consequences. For one, the whole tool is far more intimidating, and it can’t cut weeds or mow the tricky spots around trees. The edger can do jobs like trenching that aren’t possible with a weed whacker, and the wheels and guides help you cut a very straight and even edge. Think of it as a circular saw for your sod.

Even for edging, we prefer string trimmers over dedicated edgers, because they’re easier to use on curved edges or uneven ground. It’s still tricky to follow a curve perfectly, but if you lose track with a string trimmer you won’t hear the terrifying sound of a metal blade scraping against concrete.

The best trimmers make it easy to switch between horizontal cutting and edging jobs, and our top pick, the Black+Decker, is no exception. You simply hold a button on the shaft and twist the cutting head to go from grass trimming to edging quickly and easily.

Gasoline

This is the type of string trimmer you’ve seen working beside roadways. Two-cycle gas engines have all the power you could ask for and can run six hours on a gallon of gasoline. They’re loud, though, and require extra maintenance. There’s also the trouble of mixing, storing and filling the oil-gasoline mix required by two-stroke engines.

We’re not trying to dissuade anyone who needs a gas trimmer from buying one: our test partners still rely on a few reliable and powerful gas trimmers that see all-day use and perform well. For an average-sized yard, though, gasoline is overkill.

Plug-in electric

We didn’t test any corded trimmers. They have a great price-power-weight ratio, but the cord is frustrating to work with. The specialized edger/trencher we tested is a plug-in model, and it has great power, but if you’re doing anything other than straight, slow lines close to your house the cord isn’t worth it.

Battery-powered electric

Cordless electric trimming is definitely the most pleasant experience of all. These trimmers are much quieter than a gasoline-powered trimmer, and you’re free to move quickly and efficiently around your yard.

The big downside to cordless electric is capacity: battery packs make a painful trade-off between power, run-time, and weight. Lithium-based battery technology is getting better every year, so the current generation of tools is widely regarded as a worthwhile compromise if you’re doing small jobs.

Battery life is up to around half an hour for most models, long enough to finish trimming around a house and small lawn without needing to stop for a charge.

Power

In the world of cordless tools, manufacturers aren’t required to list specific power-draw specs on their tools the way they are with tools you plug into the wall. Makers do tell you about battery voltage, but that’s only half of the electrical story (volts x amps = watts).

Without a rating of the current drawn by the motor, we have to make guesses or extrapolations based on other numbers, like run-time and battery size. Gasoline engines do have a nominal watt power rating (since watts and horsepower are two different ways of measuring power, the rate work is done) and manufacturers like Stihl tell us what to expect from their engines.

We’ve made an estimate for the wattage used by each of the cordless tools. All of these numbers are for available power from the battery system and don’t take into account any waste from inefficiencies of the working machines. Our “cutting power” test scores give a better idea of what each machine can really do with that power.

A balance between power and noise

Many professionals rely on two-stroke gas trimmers for all-day landscaping work, and they might be the right tool for your job. That said, the noise of a two-stroke gasoline engine requires hearing protection and will likely disturb your family or neighbors if you like to do yard work in the morning. Some electric trimmers make a bit more noise than others, but none of them come even close to the loudness of a two-stroke engine.

Battery size

Batteries are typically sold with a capacity listed in amp-hours, literally the number of hours the battery will be able to send one ampere of electrical current to the motor. As noted above, these tools don’t list how many amps they draw from a battery, so we’ve done the dirty work with real-world tests of working time.

Cutting width and line size

The advantages of cutting a wider swath are both efficiency and power. For example, the difference between 13 inches and 15 inches might not seem like a lot, but if you’ve got large weedy patches to attack, the extra cutting with each pass can definitely add up over time.

The bigger advantage to a wider swath is in cutting power. A longer string means that, for the same engine speed, the tip of the cutting line will be moving faster, moving at (for our example) 16,000 feet per minute instead of only 14,000.

The difference between a 13-inch cutting head and a 15-inch head is about 15 percent in both the cutting area and the speed of the string, but there’s more. When you add the fact that a bigger head can take a line that has a 0.080” diameter instead of the skinny 0.065” string in a typical smaller machine, the extra mass makes for yet another 23 percent increase in the force that goes into chopping weeds. (Some big trimmers can load 0.095” or 0.1” line for even more power, and 0.095” is a typical diameter for commercial work where tough weeds are expected.)

Extra force means more electricity is needed from a battery pack, so you’ll see diminishing returns if you’re more concerned about run time than cutting a wide swath through dense weeds.

We’re pretty sure that this is the flaw in Ryobi’s design with the 40220: the motor just can’t draw enough current from a 40V battery to get the big 0.08” string going quickly enough. Our top pick from Black+Decker uses 0.065” string, but the slightly newer LST540 seem to have problems with its heavier string just like the Ryobi.

If you’re even considering running the trimmer for more than one battery charge (about half an hour) in a day, the extra width and power of a bigger trimmer with a high-voltage battery is probably worth it (and you might consider gas). If you’re mostly edging and you keep up with garden weeds so you never see half-inch stalks, then a 13-inch trimmer should do the job without extra weight or expense.

String feed system

There are a few ways to get more cutting line out when rocks, sticks, and concrete wear down or break the string:

Automatic feed: Popular on smaller trimmers, this feature is included on our top pick Black+Decker as well as the Greenworks trimmer.

This system tries to keep your line at just the right length by letting out a small amount (usually about ¼ inch) every time you stop and restart the trimmer. The line never gets too long, because a small blade chops off any excess line as it spins.

This is handy, but it can waste line if the mechanism is too generous, and can be frustrating to work with if the spool is stingy. (If you burn through a bunch of string cleaning up around a sharp-edged brick planter, for example.)

Some newer trimmers use a hybrid manual/automatic system that will pay out more line when you push a button while the trimmer is running, but this wasn’t available on the top-ranked trimmers we tested.

Manual feed: This feature lets you stop the machine, pick up the trimmer head and press a button to pull out more string. This takes time, but you can get very close to the maximum allowed length (determined by the length-trimming blade mounted on the guard) to reduce wasted line.

The trimmer from Greenworks is the only one we tested that has a manual-feed bypass for its automatic system.

Bump-feed: This lets you use a spring-loaded clutch system that will release more line when you “bump” the bottom of the trimmer head on the hard ground while it’s running. This is the system used on the 15-inch-width trimmers we tested, from Ryobi and Ego.

This takes some getting used to, but if you’re working around rocks, sticks, and concrete that quickly wear out your trimmer line, it’s a very fast way to get back to the job. Most commercial-grade trimmers use a system like this.

Fixed-line: This type of trimmer head is sometimes an option, but we didn’t pick any models with this style. Rather than a spool that feeds out line as it’s used up, a fixed-line head just holds one piece that starts out at exactly the right length and needs to be manually replaced when it wears down.

A shoulder strap

None of the models we tested came bundled with a strap, and we tested each of them without one, but if you’re going to be running a trimmer for more than ten minutes at a time you owe it to yourself to use a support system of some kind.

Essential Accessory: Arnold - Universal Trimmer Strap

The universal trimmer strap from Arnold is basic, but it’s a huge relief to shift the weight of the trimmer onto your core muscles.

See Price at Amazon

Aftermarket straps are plentiful and cheap; we tested the Arnold Universal Trimmer Strap. It works perfectly on all the models except our top pick: the bracket included with this strap won’t quite fasten around the thicker shaft on the Black+Decker tool. The strap itself can clip on various parts of the handle, though, and we didn’t have any problems using it; the Black+Decker is also a trimmer that’s light enough not to need a support strap as badly as the others do.

The shoulder strap attachment bracket should sit right at the balance point of the trimmer. After you adjust the length of the strap to get the trimmer at a perfect height, you can almost work one-handed.

There are more elaborate strap and harness systems available to help balance a heavy commercial trimmer. The trimmer will rub against your hip if you’re supporting it with a strap, so the heavy-duty harnesses include some kind of shield to fend off bruises and grass stains.

Trimming grass and weeds around your lawn is one more step in a mowing routine that can really make the difference between a lawn that’s merely cut and a lawn that looks carefully maintained.

Black+Decker’s – LST136W is a tool designed with home lawn care in mind, and it has just the right set of features and performance to excel in an urban environment. Striking a good balance in power, weight, cost, and battery capacity, this is a single-line trimmer that can keep up with your lawn-care needs.

Top Pick: Black+Decker - LST136W

At less than seven pounds and with enough battery capacity to get you through a weekly trimming job, this is a great tool for urban lawn-care.

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Daniel Jackson, Writer

Daniel is a Canadian farm boy who grew up to be a nerd with a literature degree and too many hobbies to count. He emigrated from Canada to California in 2013, and now writes for Your Best Digs full-time. Daniel remains unapologetic about Canadian spelling, serial commas, and the destruction of expensive travel mugs.