Quick answer
Our overall pick for the best string trimmer is the BLACK+DECKER 20V MAX LST300 for its balance of power, automatic feed, and 2-in-1 versatility. Other picks suit those needing a combo kit, a larger cutting path, extended runtime, or an ultra-lightweight design.
Choosing the best string trimmer for your yard means matching its capabilities to your lawn’s size and your own comfort. Cordless models have become powerful and versatile, offering features that once required a gas engine. We compared manufacturer listings and specifications for several widely available cordless string trimmers to identify picks based on key attributes like cutting width, battery system, speed, and included features.
Our picks at a glance
Pros
- Automatic Feed Spool requires no bumping
- Converts from trimmer to edger
- Lightweight with adjustable handle
- Includes battery and charger
Cons
- The listing does not mention a shoulder strap for comfort
- Smaller 12-inch cutting width compared to some models
Pros
- Includes both a string trimmer and a leaf blower
- 3-year warranty on the trimmer head
- Part of a 40V tool ecosystem
- Lightweight design noted
Cons
- The combined item weight is 16.5 pounds
- Battery runtime is listed for the whole kit, not the trimmer alone
Pros
- Folding shaft design for compact storage
- Includes two batteries
- High 9500 RPM motor speed
- Pivoting head for trimming and edging
Cons
- Total runtime is 30 minutes with both batteries
- The listing does not mention a manufacturer warranty
Pros
- Wide 16-inch cutting width
- Brushless motor for power and runtime
- Attachment-capable for system expansion
- Includes a shoulder strap and has a 4-year warranty
Cons
- At 18.7 pounds, it is one of the heavier models
- Higher voltage system may require a separate battery investment
Pros
- Long runtime of up to 63 minutes
- 13-inch cutting width
- Two-speed settings
- Converts from trimmer to edger
Cons
- The listing does not mention an automatic line feed system
- Item weight is not listed in the provided specs
Pros
- Very lightweight at 3.5 lbs
- Includes two batteries for extended runtime
- Auto feed and pivoting head
- Quiet operation noted
Cons
- Key specs like cutting width and dimensions in the data are implausible
- The listing does not mention a warranty
How we chose
We compared manufacturer listings and specifications on Amazon as of October 2026, focusing on objective data. We did not conduct hands-on testing. Our criteria included cutting width, motor speed (RPM), battery type and runtime, weight, included features like automatic feed and edging capability, and warranty information.
Best Cordless String Trimmers: our picks in detail
1. Best overall: BLACK+DECKER LST300 20V MAX
The BLACK+DECKER LST300 is a 20V cordless string trimmer with a 12-inch steel deck. It features a POWERDRIVE Transmission that delivers a speed of 6200 RPM. Its key feature is an Automatic Feed Spool (AFS) that feeds line without bumping. The tool converts from a trimmer to an edger in seconds.
It has a lightweight design with adjustable handle and height positions. The kit includes one 2.0 Ah lithium-ion battery and charger. The manufacturer provides a 2-year limited warranty.
Best for: This is our pick for the best string trimmer overall due to its proven automatic feed system, straightforward 2-in-1 edging capability, and included battery.
Pros
- Automatic Feed Spool requires no bumping
- Converts from trimmer to edger
- Lightweight with adjustable handle
- Includes battery and charger
Cons
- The listing does not mention a shoulder strap for comfort
- Smaller 12-inch cutting width compared to some models
2. Best for a combo kit: Greenworks 40V 12″ Trimmer & Blower Combo
The Greenworks STBA40B210 is a 40V combo kit that includes a 12-inch string trimmer and a 390 CFM leaf blower. The trimmer has a commercial-grade head with .065″ auto-feed line and a 3-year head warranty. It operates at 7500 RPM.
The kit runs on a universal 40V 2.0Ah battery with a 60-minute charge time. The listing states the balanced design is 30% lighter than gas alternatives. The blower features cruise control and operates at 110 MPH. The entire combo has a 3-year warranty.
Best for: This is the best string trimmer for those who want a versatile lawn maintenance combo kit with a powerful blower included.
Pros
- Includes both a string trimmer and a leaf blower
- 3-year warranty on the trimmer head
- Part of a 40V tool ecosystem
- Lightweight design noted
Cons
- The combined item weight is 16.5 pounds
- Battery runtime is listed for the whole kit, not the trimmer alone
3. Best for compact storage: KOMASTY 20V Foldable String Trimmer
The KOMASTY cordless string trimmer has a 12-inch cutting width and a motor speed of 9500 RPM. Its key feature is a shaft that folds 180° in three ways for vertical storage. The head adjusts 90° and the handle rotates 180° for hard-to-reach areas.
It includes two 2.0Ah batteries and a charger, providing a total of up to 30 minutes of continuous runtime. It has an automatic line feed system and functions as a 2-in-1 trimmer and edger.
Best for: This is the best string trimmer for apartments or homes with limited garage or shed space due to its innovative foldable shaft.
Pros
- Folding shaft design for compact storage
- Includes two batteries
- High 9500 RPM motor speed
- Pivoting head for trimming and edging
Cons
- Total runtime is 30 minutes with both batteries
- The listing does not mention a manufacturer warranty
4. Best for large yards: Greenworks 60V 16″ Brushless String Trimmer
The Greenworks ST60L413 is a 60V brushless cordless string trimmer with a wide 16-inch cutting path. It operates at 10000 RPM and is designed for thicker grass. It features an attachment-capable shaft for connecting other Greenworks tools.
It includes a Load N’ Go head for quick line reloading and comes with an adjustable shoulder strap. The kit includes a 4.0Ah battery, charger, and spool, and is backed by a 4-year limited warranty covering both tool and battery.
Best for: This is the best string trimmer for medium to large yards thanks to its wide 16-inch cutting path and powerful 60V brushless motor.
Pros
- Wide 16-inch cutting width
- Brushless motor for power and runtime
- Attachment-capable for system expansion
- Includes a shoulder strap and has a 4-year warranty
Cons
- At 18.7 pounds, it is one of the heavier models
- Higher voltage system may require a separate battery investment
5. Best for extended runtime: CRAFTSMAN V20 13″ String Trimmer
The CRAFTSMAN CMCST901M1 is a 20V cordless string trimmer with a 13-inch cutting swath. It offers up to 63 minutes of runtime with its included 4Ah battery. The motor is noted to provide 52% more power than previous models.
It features an adjustable handle, Turn-To-Edge functionality for converting to an edger, and two speed settings to prioritize either runtime or power. The item weight is not listed in the provided specifications.
Best for: This is the best string trimmer for users who need long, uninterrupted runtime on a single battery charge.
Pros
- Long runtime of up to 63 minutes
- 13-inch cutting width
- Two-speed settings
- Converts from trimmer to edger
Cons
- The listing does not mention an automatic line feed system
- Item weight is not listed in the provided specs
6. Best for lightweight ease: GOODJOB 20V Ultra-Lightweight String Trimmer
The GOODJOB cordless weed wacker is noted for an ultra-lightweight design of 3.5 lbs. It is a 20V system with a 12-inch cutting width and functions as a 3-in-1 string trimmer, lawn edger, and weed cutter. It features an auto feed system and a 180° pivoting head.
The kit includes two 2.0Ah batteries and a quick charger, providing 40-60 minutes of total runtime. It operates quietly below 75 dB and has a built-in safety switch. The provided cutting width and item dimensions in the specs appear to be placeholder data.
Best for: This is the best string trimmer for users who prioritize a very lightweight tool to reduce fatigue during yard work.
Pros
- Very lightweight at 3.5 lbs
- Includes two batteries for extended runtime
- Auto feed and pivoting head
- Quiet operation noted
Cons
- Key specs like cutting width and dimensions in the data are implausible
- The listing does not mention a warranty
Cordless string trimmers at a glance
| Model | Voltage | Cutting Width | Battery Runtime | Key Feature |
|---|---|---|---|---|
| BLACK+DECKER LST300 | 20V | 12 inches | Not listed | Automatic Feed Spool |
| Greenworks 40V Combo | 40V | 12 inches | 2 hours (kit) | Includes leaf blower |
| KOMASTY Foldable | 20V | 12 inches | 30 min (total) | Folding shaft |
| Greenworks 60V | 60V | 16 inches | Not listed | Attachment capable |
| CRAFTSMAN V20 | 20V | 13 inches | 63 minutes | Two-speed settings |
| GOODJOB Ultra-Light | 20V | Not listed* | 40-60 min (total) | 3.5 lb weight |
*The listing title states 12″, but the spec field contains an implausible value.
How to choose a cordless string trimmer
Selecting the best string trimmer involves more than just power. The right tool should make your lawn maintenance easier, not add to the chore. Start by considering the size of the area you need to trim. A wider cutting path, like 16 inches, covers more ground quickly for larger yards, while a standard 12- or 13-inch width is sufficient for most suburban lawns.
Battery voltage and runtime are closely linked. Higher voltage systems (like 40V or 60V) often deliver more consistent power for tough weeds, but the battery’s amp-hour (Ah) rating directly impacts how long you can run the tool. Look for kits that include a battery and charger. Features like automatic line feed save time and hassle, and a tool that converts to an edger adds versatility. For comfort, adjustable handles and lightweight designs are key, and a shoulder strap can be a major benefit for larger properties.
What to look for
- Cutting Width: Match the swath to your yard size; 12-13 inches is standard, 16 inches is for larger areas.
- Battery System: Consider voltage for power and amp-hours (Ah) for runtime. Check if the battery works with other tools you own.
- Line Feed: Automatic feed systems (AFS) dispense line without needing to bump the head on the ground.
- Versatility: A 2-in-1 trimmer/edger saves you from needing a separate tool for crisp lawn edges.
- Comfort: Adjustable handles, lightweight construction, and shoulder straps reduce fatigue.
Remember, a string trimmer is just one part of a complete lawn care equipment arsenal. For other tasks like improving soil health, you might consider aeration or dethatching.
FAQ
What’s the advantage of an automatic feed spool?
An automatic feed spool (AFS) advances the trimmer line as it wears down, without requiring you to tap or “bump” the head on the ground. This feature provides a more consistent cutting length and can make the trimming process smoother and less interrupted.
Is a higher RPM always better for a string trimmer?
Not necessarily. A higher RPM (revolutions per minute) indicates a faster spinning cutting head, which can help with cutting through tough, thick grass. However, effective cutting also depends on the trimmer line thickness, motor torque, and overall design. For most residential lawns, a range between 6000 and 9000 RPM is common and effective.
Can I use a string trimmer for edging?
Many cordless string trimmers are 2-in-1 tools that can convert to an edger, usually by rotating the head or shaft. This allows you to create clean borders along walkways and garden beds. If this feature is important, look for models that specifically mention “edger” or “2-in-1” functionality in their listing.
How do I maintain my cordless string trimmer?
Always follow the safety and maintenance instructions in the manufacturer’s manual. General maintenance includes keeping the air vents clear of debris, checking for damage to the shaft and head, cleaning the tool after use, and storing the battery in a cool, dry place. Ensure you use the correct diameter and type of replacement trimmer line.
References
- Amazon product listings and manufacturer specifications (accessed October 2026)
- U.S. Environmental Protection Agency, Emission Standards Reference Guide
- Outdoor Power Equipment Institute (OPEI)
