20v vs 40v String Trimmer: Which One Should You Buy?
Two 20V combos and two 40V bare-tool trimmers compared by stated cutting width, weight and kit contents, for lawn edges and borders.
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Top picks at a glance
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- 1
Litheli 20V Cordless Hedge Trimmer9.7/10View on Amazon - 2
Makita GRU01Z 40V max XGT® Brushless Cordless 15" String9.5/10View on Amazon - 3
BLACK+DECKER 40V MAX 13 in String Trimmer Edger Cordless with9.5/10View on Amazon - 4
beyond by BLACK+DECKER 20V MAX String Trimmer / EdgerView on Amazon - 5
Dewalt Trimmer Hedge Bare 20V DCHT820BView on Amazon - 6
BLACK+DECKER 3-in-1 String Trimmer/Edger & Lawn MowerView on Amazon - 7
Oregon Magnum Gatorline 095 Trimmer Line Heavy DutyView on Amazon - 8
BLACK+DECKER String Trimmer / EdgerView on Amazon - 9
Husqvarna 130L Gas String TrimmerView on Amazon
Verdict: Choose a 20v trimmer if you want a kit with a battery and charger in the box. Choose a 40v trimmer if you already own a compatible battery, since both 40v examples here are bare tools, and compare cutting width listing by listing, since width does not follow voltage.
The edges of the property set the job: neat borders around walks and beds, or thick grass along fences and ditches. This comparison looks at 20v vs 40v string trimmer options, and the split is not voltage alone, since the kits and the bare tools differ in what comes in the box. The listings make that split clear alongside cutting width.
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BLACK+DECKER 20V MAX Weed Eater, Edger and Sweeper Combo
A 20V combo kit with a trimmer that converts to a wheeled edger, plus a sweeper, two batteries and a charger.
Read the full review
The listing states a 20V MAX combo kit with a string trimmer that converts to a wheeled edger, plus a sweeper, two 1.5Ah batteries and a charger. The trimmer weighs 4.5 pounds and cuts 10 inches, the sweeper weighs 3.7 pounds and is rated at 130 mph for hard surfaces, and the kit item weight is 10.5 pounds. It states AFS automatic line feed, adjustable height and handle, and a 2 Year Limited Warranty.
Pros
- Combo: trimmer converting to a wheeled edger, plus a sweeper in one kit
- Two 1.5Ah batteries and charger included
- AFS automatic line feed
- 2 Year Limited Warranty stated
Cons
- 10 inch cutting width is the narrowest here
- Sweeper described for hard surfaces, with no other surface stated
- Kit item weight of 10.5 pounds covers both tools, not the trimmer alone
- No trimmer line diameter is stated
Greenworks 40V 15-Inch Torqdrive String Trimmer
A 40V bare-tool trimmer with a 15 inch cutting path, dual line bump feed and a 2 speed selector.
Read the full review
The listing states a 40V 15 inch Torqdrive string trimmer, battery and charger not included, with a 15 inch cutting path, dual line .080 inch bump feed head, variable speed trigger, 2 speed selector switch and 5500 rpm. It weighs 9.2 pounds.
Pros
- 15 inch cutting path, widest here
- TORQDRIVE design with a stated 30% more torque claim
- Dual line .080 inch bump feed head
- 2 speed selector for power or runtime
Cons
- Battery and charger not included
- No warranty term is stated
- Heaviest stated weight here at 9.2 pounds
- No edger conversion stated
Greenworks 40V 12-Inch Cordless String Trimmer
A 40V bare-tool trimmer with a 12 inch cutting path, auto feed head and variable speed trigger.
Read the full review
The listing states a 40V 12 inch cordless string trimmer, battery and charger not included, with a 12 inch cutting path, .065 inch line, auto feed head and variable speed trigger. It weighs 8.4 pounds and names compatible GreenWorks G-MAX 40V battery models 29472 and 29462 and charger model 29482.
Pros
- Listing claims it powers through the toughest grass and weeds
- 12 inch cutting path with .065 inch line and auto feed head
- Variable speed trigger
- Ultra lightweight design described in the listing, at 8.4 pounds
Cons
- Battery and charger not included
- No warranty term is stated
- 12 inch cutting path is narrower than the 15 inch example
- No blower or edger included
DEWALT 20V MAX String Trimmer and Leaf Blower Kit
A 20V combo kit with a string trimmer and leaf blower, battery and charger included.
Read the full review
The listing states a DEWALT 20V MAX string trimmer and leaf blower kit, cordless, with battery and charger included, and a cutting width of 13 inches. Two spec table figures do not fit the kit: the power source is listed as Hand_powered against the cordless title, and the item weight is listed as 20 g, which is not credible for a trimmer and blower kit. No usable weight is stated, so none is reported here.
Pros
- Combo kit: trimmer and blower with battery and charger
- 13 inch cutting width
- Cordless kit for lawns, gardens and outdoor spaces
- Battery and charger included in the box
Cons
- Bullets name only model numbers, no features stated
- Spec table power source says Hand_powered, against the cordless title
- Spec table weight of 20 g is not credible for a kit
- No warranty term is stated
Other machines to compare
beyond by BLACK+DECKER 20V MAX String Trimmer / EdgerCheck price on Amazon
Dewalt Trimmer Hedge Bare 20V DCHT820BCheck price on Amazon
BLACK+DECKER 3-in-1 String Trimmer/Edger & Lawn MowerCheck price on Amazon
Oregon Magnum Gatorline 095 Trimmer Line Heavy DutyCheck price on Amazon
BLACK+DECKER String Trimmer / EdgerCheck price on Amazon
Husqvarna 130L Gas String TrimmerCheck price on Amazon
20v vs 40v string trimmer side by side
| Trimmer | Acre Score | Cutting width | Weight |
|---|---|---|---|
| BLACK+DECKER LCC222 | 9.6/10 | 10 inches | 4.5 pounds |
| Greenworks ST40B04 | 9.5/10 | 15 inches | 9.2 pounds |
| Greenworks BST4000 | 9.4/10 | 12 inches | 8.4 pounds |
| DEWALT DCKO215M1 | 9.4/10 | 13 inches | Not stated |
Example figures are manufacturer stated, collected 25 October 2026.
Voltage and what it powers
Voltage alone does not decide the cut. The 20v side here is two combo kits: the BLACK+DECKER kit is a trimmer that converts to a wheeled edger, plus a sweeper, and the DEWALT kit pairs a trimmer with a leaf blower. The 40v side is two bare-tool trimmers: the Greenworks 12 inch and 15 inch examples, both without battery or charger. A buyer comparing voltage must also compare what is in the box.
Cutting width and line
Cutting width follows the listing, not the voltage. The BLACK+DECKER example cuts 10 inches, the DEWALT example cuts 13 inches, the Greenworks 12 inch example cuts 12 inches with .065 inch line and an auto feed head, and the Greenworks 15 inch example cuts 15 inches with dual .080 inch line and a bump feed head. The widest cut here is a 40v example, but the second widest is a 20v example, so width does not follow voltage.
Weight and handling
Tool weight is stated for three examples: the BLACK+DECKER trimmer weighs 4.5 pounds, the Greenworks 12 inch example weighs 8.4 pounds, and the Greenworks 15 inch example weighs 9.2 pounds. The DEWALT listing states no usable weight, since its spec table lists 20 g for a trimmer and blower kit. The BLACK+DECKER example also states an adjustable height and handle, and both Greenworks examples state a variable speed trigger.
Bare tool or kit
The box contents split the sides. Both 20v examples include a battery and charger: the BLACK+DECKER kit includes two 1.5Ah batteries, and the DEWALT kit includes one battery. Both 40v examples are bare tools with battery and charger not included, and the 12 inch example names compatible GreenWorks G-MAX 40V battery models 29472 and 29462 and charger model 29482. A bare tool suits a buyer who already owns a compatible battery, since no battery or charger comes in the box.
Four examples: 20v vs 40v string trimmer
Matching It to Your Property
- For walks and beds, the BLACK+DECKER kit converts to a wheeled edger for precise borders.
- For thick grass, the Greenworks 15 inch example states a TORQDRIVE design with a stated 30% more torque claim, with no baseline stated in the listing.
- For storage, a combo kit means two tools to store, while a bare tool means one tool plus a separately owned battery and charger to store.
- For larger lawns, the BLACK+DECKER kit includes a second battery for extended coverage.
The Acre Score explained
The Acre Score weighs performance, build, value, safety and warranty. No listing here states a safety certification, so all four examples score zero on safety. One listing states a warranty: the BLACK+DECKER example carries a 2 Year Limited Warranty. How we pick explains the weights.
| Product | Acre Score | Perf. /35 | Build /25 | Value /25 | Safety /10 | Warranty /5 |
|---|---|---|---|---|---|---|
| BLACK+DECKER LCC222 | 9.6 | 30 | 21 | 22 | 0 | 3 |
| Greenworks ST40B04 | 9.5 | 30 | 21 | 19 | 0 | 0 |
| Greenworks BST4000 | 9.4 | 28 | 20 | 19 | 0 | 0 |
| DEWALT DCKO215M1 | 9.4 | 26 | 19 | 20 | 0 | 0 |
Scores run from 9.2 to 9.8: each product’s point total is placed on that range, so more points always means a higher score.
Wear eye and hearing protection, long pants and sturdy footwear, and keep bystanders well back while the line or blade spins. Clear stones and debris first, and stop the engine or remove the battery before clearing the head. Refuel only with the engine off and cool. See OSHA landscaping safety. Read our Safety Disclaimer.
FAQ: mowing large lots
Does higher voltage mean a wider cut?
No. The 20v examples cut 10 and 13 inches, and the 40v examples cut 12 and 15 inches, so width follows the listing, not the voltage.
Do the 40v examples include a battery?
No. Both Greenworks examples are bare tools with battery and charger not included.
Which examples include a blower?
The BLACK+DECKER kit includes a sweeper rated at 130 mph for hard surfaces, and the DEWALT kit includes a leaf blower. The Greenworks examples are trimmers only.
Which one has a warranty?
The BLACK+DECKER listing states a 2 Year Limited Warranty. The other three listings state no warranty term.
Can the 20v examples edge?
The BLACK+DECKER example converts to a wheeled edger. The DEWALT listing states no edger conversion.
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