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Finding the best string trimmers with 4 0 ah requires looking at the numbers. This guide compares 10 models based strictly on their published specifications. The EGO Power+ 16-Inch Carbon Fiber String Trimmer leads the list. It offers a 16-inch cutting width and 56V power for users wanting wide coverage. Each pick reflects specific data points like voltage and motor type. You can use these specs to match a tool to your yard size. Read on to decide which battery-powered trimmer fits your needs.
Match Voltage to Your Existing Battery
Your 4.0 Ah battery only works with one voltage system. The EGO Power+ uses 56V, while Makita and Ryobi models run on 18V or 40V. Choose the tool that matches your current platform. This ensures you can swap batteries between the trimmer and other gear without buying extra packs.
| # | Product | Best for | Price |
|---|---|---|---|
| 1 | EGO Power+ 16-Inch Carbon Fiber String Trimmer Best overall | users wanting a wide 16-inch cut | |
| 2 | Makita 13-Inch Brushless Trimmer Best 13-inch | Users with existing Makita 18V batteries | |
| 3 | Husqvarna 320iL String Trimmer and 230iB Leaf Blower Bundle Best premium | matched trimmer and blower sets | |
| 4 | Makita 15-Inch Brushless String Trimmer Best budget | users who want automatic torque management | |
| 5 | Makita 13-Inch Brushless String Trimmer Best 20-inch | Trimming and hedging with one power head | |
| 6 | Ryobi 40V Cordless String Trimmer and Blower Kit Also great | Users wanting a 40V trimmer and blower combo | |
| 7 | WORX 12-Inch Cordless String Trimmer Also great | shared battery mowing and trimming kits | |
| 8 | Greenworks 40V Brushless Combo Also great | precise edging and weed trimming | |
| 9 | WORX 20V 12" Cordless Trimmer Best 2-in-1 | Users wanting a combined trimmer and mower kit | |
| 10 | DEWALT 20V MAX Brushless String Trimmer Also great | Small yards needing trim and blow in one kit |
The best fit for you
- You want the widest cutting width available – EGO Power+ 16-Inch Carbon Fiber String Trimmer – It features a 16-inch cutting width for covering more ground per pass.
- You already own Makita 18V batteries – Makita 13-Inch Brushless Trimmer – It uses the 18V LXT ecosystem, allowing you to share your existing 4.0 Ah battery.
- You need a matched trimmer and blower set – Husqvarna 320iL String Trimmer and 230iB Leaf Blower Bundle – This bundle includes the 320iL trimmer and 230iB blower, both powered by the 4.0 Ah battery.
- You want to trim and hedge with one head – Makita 13-Inch Brushless String Trimmer – It is a couple-shaft design that accepts multiple attachments for versatile yard work.
EGO Power+ 16-Inch Carbon Fiber String Trimmer
Best for: users wanting a wide 16-inch cut
- Battery Capacity
- 4.0 Ah
- Cutting Width
- 16"
- Voltage
- 56V
- Line Feed System
- Auto-sensing
- Shaft Type
- Telescopic
- Power Type
- Cordless
This EGO POWER+ trimmer features a 56V system and a 16-inch cutting width. It includes a 4.0Ah battery for up to 60 minutes of runtime. The telescopic carbon fiber shaft adjusts to your height. Auto-sensing line feed keeps the cutting swath continuous. This model suits users seeking durable, long-lasting trimming with minimal interruption.
- 56V voltage provides high power output
- 16-inch cutting width covers more area per pass
- Telescopic carbon fiber shaft adjusts for user height
- Auto-sensing line feed eliminates bump-to-feed stops
- Up to 60 minutes of runtime on a 4.0Ah battery
- 16-inch cutting width is narrower than some competing 17-inch models
- 56V system uses proprietary batteries rather than 40V or 20V platforms
- Carbon fiber shaft adds weight compared to standard plastic shafts
- You want a wide 16-inch cutting swath for faster trimming
- You prefer a telescopic shaft to adjust for your height
- You already own or plan to buy EGO 56V batteries
- You need a cutting width wider than 16 inches
- You prefer a 40V or 20V battery ecosystem
- You want a lightweight plastic shaft for extended overhead use
Verdict: EGO POWER+ 16" Cordless String Trimmer delivers strong 56V performance and a wide 16-inch cut. It fits users who value height-adjustable carbon fiber shafts and continuous auto-sensing line feed.
Makita 13-Inch Brushless Trimmer
Best for: Users with existing Makita 18V batteries
- Battery Capacity
- 4.0 Ah
- Cutting Width
- 13"
- Voltage
- 18V
- Motor Type
- Brushless
- Power Type
- Cordless
- Dimensions
- 8.23 × 40 × 7.36 inches
This Makita kit pairs an 18V brushless power head with a 13-inch string trimmer attachment. It runs on a 4.0 Ah battery and delivers up to 7,000 RPM. The lever-style lock system allows for quick, tool-less installation of attachments. You get a compact, gas-free tool that eliminates emissions and pull starts. It fits users who prefer a versatile power head system with a moderate cutting width.
- Brushless motor delivers up to 7,000 RPM
- 13-inch cutting width for moderate trimming tasks
- Tool-less lever lock for quick attachment swaps
- Runs on a 4.0 Ah battery
- 18V voltage is lower than the 40V and 20V MAX options on this list
- 13-inch cutting width is narrower than the 16-inch and 17-inch competitors
- You already own Makita 18V LXT batteries and want to share power sources
- You need a versatile power head that accepts multiple attachments like a pole saw
- You prefer a compact, lightweight tool for detailed trimming work
- You require the widest possible cutting deck for large, open yards
- You need the highest voltage for maximum power in tough conditions
- You want a dedicated, single-purpose string trimmer without extra attachments
Verdict: Makita 13-Inch Brushless String Trimmer suits users who value system versatility and a moderate 13-inch cut. It is ideal for those who already invest in the 18V LXT ecosystem and want a compact tool for precise work.
Husqvarna 320iL String Trimmer and 230iB Leaf Blower Bundle
Best for: matched trimmer and blower sets
- Battery Capacity
- 4.0 Ah
- Cutting Width
- 16-inch
- Power Type
- Electric
- Included Equipment
- Leaf Blower
- Dimensions
- 37.4 × 10 × 5 inches
This bundle pairs a 16-inch cutting width string trimmer with a leaf blower, both using a 4.0 Ah battery. The trimmer features a 16-inch deck and active cooling for consistent power. The blower delivers 650 CFM of airflow. You get a complete yard care kit in one purchase. The system includes a charger and a specific battery model. It is designed for users who want multiple tools from one brand ecosystem.
- 16-inch cutting width for efficient trimming
- Leaf blower produces 650 CFM airflow
- Active cooling system maintains consistent power
- Boost mode adds 20% extra power when needed
- Trimmer deck is 16 inches, smaller than the 17-inch options on this list
- Blower weight is 8.4 lbs, heavier than the 5.5 lb blower in the Worx kit
- You want a string trimmer and leaf blower from the same brand
- You need a 16-inch cutting width for general yard work
- You prefer active cooling for longer runtime
- You need a cutting width larger than 16 inches
- You only need a string trimmer without a blower
Verdict: Husqvarna 320iL & 230iB Bundle fits users who want a matched trimmer and blower set with active cooling. It suits those who value the 16-inch cutting width and 650 CFM blower output over larger deck sizes or lighter individual tools.
Makita 15-Inch Brushless String Trimmer
Best for: users who want automatic torque management
- Battery Capacity
- 4.0 Ah
- Cutting Width
- 15"
- Voltage
- 40V max
- Motor Type
- Brushless
- Power Type
- Cordless
- Dimensions
- 7.09 × 72.4 × 8.9 inches
This Makita string trimmer features a 15-inch cutting swath and a brushless motor. It runs on a 40V max 4.0Ah battery, offering up to one hour of runtime. The tool includes Automatic Torque Drive Technology, which shifts RPMs to balance power and efficiency. It is designed for users who want sustained performance under heavy loads thanks to XGT digital communication.
- 15-inch cutting width for increased productivity
- Brushless motor provides high power and torque
- Up to 1 hour of runtime with 4.0Ah battery
- Automatic Torque Drive shifts 3,500-6,500 RPM
- 15-inch cutting width is narrower than the 16-inch and 17-inch options on this list
- 40V max voltage is lower than the 40V and 40V Power Share systems used by other products
- You need a trimmer with a 15-inch cutting swath
- You want up to one hour of runtime on a 4.0Ah battery
- You prefer automatic torque adjustment for heavy loads
- You require a cutting width wider than 15 inches
- You prefer a 20V or 18V system over 40V
- You need a model with a 17-inch or 16-inch cutting width
Verdict: Makita 15" 40V Brushless String Trimmer suits users who prioritize automatic torque management and a 15-inch cut. It is a solid pick for those who do not need the widest available cutting swath.
Makita 13-Inch Brushless String Trimmer
Best for: Trimming and hedging with one power head
- Battery Capacity
- 4.0 Ah
- Cutting Width
- 13"
- Voltage
- 18V
- Motor Type
- Brushless
- Power Type
- Cordless
- Dimensions
- 11 × 44.9 × 7.52 inches
This Makita kit uses an 18V brushless power head with a 4.0 Ah battery. It includes a 13-inch string trimmer attachment. The lever lock system allows for quick tool-less changes. You get a 20-inch hedge trimmer attachment as well. This setup suits users who want versatility from one power source. The brushless motor provides up to 7,000 RPM for trimming.
- Brushless motor delivers up to 7,000 RPM
- Includes 13-inch string trimmer attachment
- Includes 20-inch articulating hedge trimmer attachment
- Lever style lock for tool-less installation
- 4.0 Ah battery capacity
- 13-inch cutting width is narrower than the 16-inch and 17-inch options on this list
- 18V voltage is lower than the 40V systems available elsewhere in this guide
- You need a dual-purpose tool for both trimming and hedging
- You already own Makita 18V LXT batteries
- You prefer a compact 13-inch cutting path for tight spaces
- You require a wider 16-inch or 17-inch cutting deck
- You need higher voltage power for larger yards
- You want a dedicated single-purpose trimmer without attachments
Verdict: Makita 18V Brushless Couple Shaft Trimmer fits users who want to trim and hedge with one power head. It is ideal for those who value the 4.0 Ah battery and lever-lock versatility over raw cutting width.
Ryobi 40V Cordless String Trimmer and Blower Kit
Best for: Users wanting a 40V trimmer and blower combo
- Battery Capacity
- 4.0 Ah
- Voltage
- 40V
- Shaft Type
- Attachment-capable
- Power Type
- Cordless
- Included Equipment
- Leaf Blower
- Dimensions
- 36 × 9 × 14 inches
This Ryobi kit pairs a string trimmer with a leaf blower, both powered by a 4.0 Ah battery. The blower delivers 155 MPH air speed and 300 CFM volume. It features an attachment-capable shaft for future tools. The 40V platform supports over 50 compatible devices. You get a 5-year warranty on tools and 3 years on batteries. It suits users wanting a complete yard care solution.
- Includes both string trimmer and leaf blower
- 40V system with 4.0 Ah battery
- 155 MPH blower air speed
- 300 CFM blower volume
- Attachment-capable shaft design
- Lower blower speed than many single-tool competitors
- Heavier build at 1.52 pounds for the tool
- Requires purchasing separate 40V tools for expansion
- You need a string trimmer and leaf blower in one purchase
- You plan to expand your yard tool collection with 40V devices
- You prefer a 4.0 Ah battery capacity for runtime
- You only need a string trimmer and want to save money
- You require a brushless motor for maximum efficiency
- You prefer a single-purpose tool over a combo kit
Verdict: Ryobi 40V 2-Tool Combo Kit is a practical choice for homeowners who want a string trimmer and leaf blower paired with a 4.0 Ah battery. It fits users who value the 40V ecosystem and attachment-capable design for future expansion.
WORX 12-Inch Cordless String Trimmer
Best for: shared battery mowing and trimming kits
- Battery Capacity
- 4.0 Ah
- Cutting Width
- 12 in
- Voltage
- 20V
- Line Feed System
- Push-button
- Power Type
- Cordless
- Included Equipment
- Edger
This kit pairs a 17-inch 40V mower with a 12-inch 20V trimmer. Both use the 4.0 Ah battery capacity for shared power. The mower features Intellicut technology to adjust torque based on grass thickness. The trimmer converts to an edger and uses a push-button line feed system. You get a versatile setup that covers mowing and trimming tasks with a single battery platform.
- 17-inch cutting width for efficient mowing
- 40V mower uses Intellicut torque technology
- 12-inch trimmer converts to wheel edger
- Push-button line feed system on trimmer
- Shared 4.0 Ah battery across both tools
- Trimmer has a narrower 12-inch cutting width
- Trimmer runs on lower 20V voltage
- You want a mower and trimmer that share batteries
- You need a trimmer that also functions as an edger
- You prefer torque adjustment for thick grass
- You only need a string trimmer and no mower
- You require a wider 15-inch or larger cutting path
- You prefer a single-voltage system for all tools
Verdict: WORX 17" 40V Mower & 12" 20V Trimmer fits homeowners who want to mow and trim with one battery system. It is best for those who value the convenience of a convertible edger and adjustable mower torque.
Greenworks 40V Brushless Combo
Best for: precise edging and weed trimming
- Battery Capacity
- 4.0 Ah
- Cutting Width
- 12 in
- Voltage
- 40V
- Line Feed System
- Auto feed
- Power Type
- Cordless
- Motor Type
- Brushless
This Greenworks kit combines a 40V brushless edger and a 12-inch string trimmer. It includes a 4.0Ah battery that supports up to 60 minutes of runtime. The edger features an 8-inch blade with tool-less depth adjustment. The trimmer uses an auto-feed head for consistent line advancement. You get a versatile setup for maintaining lawn edges and clearing weeds.
- Brushless motor provides more torque and longer life
- Includes a 4.0Ah battery for extended runtime
- 8-inch edger blade with curb wheel for precision
- Tool-less depth adjustment for added control
- 12-inch cutting path is narrower than competitors
- 40V voltage is lower than the 48V or 80V options on this list
- You want a dedicated tool for precise lawn edging
- You need a lightweight kit for reduced user fatigue
- You already own Greenworks 40V batteries
- You require a wider cutting width for large areas
- You prefer higher voltage for maximum power
- You only need a string trimmer without an edger
Verdict: Greenworks 40V Brushless Edger & Trimmer Kit suits homeowners who value precise edging alongside weed trimming. It offers a practical two-in-one solution for maintaining clean lawn borders and clear walkways.
WORX 20V 12" Cordless Trimmer
Best for: Users wanting a combined trimmer and mower kit
- Battery Capacity
- 4.0 Ah
- Cutting Width
- 12"
- Voltage
- 20V
- Line Feed System
- Push button command feed
- Power Type
- Cordless
- Mowing Functions
- 2-in-1
The WORX WG911 combines a 12-inch string trimmer and a 17-inch lawn mower in one kit. It uses 20V and 40V batteries with 4.0 Ah capacity. The trimmer converts to an edger and tilts 90 degrees for slopes. The mower features intellicut technology for thick grass. This bundle suits users wanting two tools in one package.
- Converts from trimmer to wheel edger in seconds
- Trimmer head tilts 90 degrees for sloped terrain
- Intellicut technology adds power for thick grass
- Single-lever adjustment offers six cutting heights
- Push button command feed system for instant line
- 12-inch cutting width is narrower than other list trimmers
- 20V trimmer voltage is lower than 40V or 40V max competitors
- 17-inch mower deck is smaller than 20-inch options
- You need a trimmer that converts to an edger
- You want to mow and trim with one battery system
- You have sloped terrain requiring a tilting head
- You prefer a wider 16-inch or larger cutting width
- You need higher voltage for maximum trimmer power
- You only want a dedicated string trimmer without a mower
Verdict: The WORX WG911 12-Inch Trimmer Mower Kit fits users who want to mow and trim with a single kit. It is ideal for small to medium lawns where versatility matters more than maximum cutting width.
DEWALT 20V MAX Brushless String Trimmer
Best for: Small yards needing trim and blow in one kit
- Battery Capacity
- 4.0 Ah
- Cutting Width
- 13 inches
- Voltage
- 20V MAX
- Line Diameter
- 0.080 inches
- Power Type
- Cordless
- Motor Type
- Brushless
This DEWALT kit pairs a 20V MAX brushless string trimmer with a handheld leaf blower. The trimmer features a 13-inch cutting swath and uses 0.080-inch line. It includes a 4.0 Ah battery. The unit weighs 15 pounds. You get variable speed control and a gear drive transmission. This setup suits users who want a compact tool for smaller yards or detailed edge work.
- Brushless motor for efficiency
- 13-inch cutting width
- Variable high/low speed trigger
- Includes leaf blower
- Gear drive transmission
- 13-inch cutting swath is narrower than the 15-inch or 16-inch options on this list
- 20V MAX system offers less power than the 40V or 18V LXT systems used by other picks
- 15-pound weight is higher than some lighter competitors
- You need a dual-purpose tool for trimming and blowing
- You prefer a compact 13-inch cutting width for precision
- You already own 20V MAX DEWALT batteries
- You require a wider 15-inch or 16-inch cutting path
- You need the higher power output of a 40V system
- You want a dedicated trimmer without a leaf blower
Verdict: DEWALT 20V 4 Ah Brushless String Trimmer delivers a compact, dual-function solution for light-duty maintenance. It fits buyers who value versatility and precision over raw power or wide coverage. This kit is ideal for small yards where maneuverability matters most.
Specifications side by side
| Spec | EGO Power+ 16-Inch Carbon Fiber String Trimmer | Makita 13-Inch Brushless Trimmer | Husqvarna 320iL String Trimmer and 230iB Leaf Blower Bundle | Makita 15-Inch Brushless String Trimmer | Makita 13-Inch Brushless String Trimmer | Ryobi 40V Cordless String Trimmer and Blower Kit | WORX 12-Inch Cordless String Trimmer | Greenworks 40V Brushless Combo | WORX 20V 12" Cordless Trimmer | DEWALT 20V MAX Brushless String Trimmer |
|---|---|---|---|---|---|---|---|---|---|---|
| Cutting Width | 16" | 13" | 16-inch | 15" | 13" | – | 12 in | 12 in | 12" | 13 inches |
| Voltage | 56V | 18V | – | 40V max | 18V | 40V | 20V | 40V | 20V | 20V MAX |
| Battery Capacity | 4.0Ah, 2.5Ah | 4.0Ah | 4 Ah | 4.0Ah | 4.0Ah | 4.0 Ah | – | 2.0Ah | 4.0Ah | 4 Ah |
| Motor Type | – | Brushless | – | Brushless | Brushless | – | – | – | – | – |
| Line Feed System | Auto-sensing | – | – | – | – | – | Push-button | Auto feed | Push button command feed | – |
| Line Diameter | – | – | – | – | – | – | – | – | – | 0.080 inches |
| Shaft Type | Telescopic | – | – | – | – | Attachment-capable | – | – | – | – |
| Power Type | Cordless | Cordless | Electric | Cordless | Cordless | Cordless | Cordless | Cordless | Cordless | Cordless |
| Mowing Functions | – | – | – | – | – | – | – | – | 2-in-1 | – |
| Included Equipment | – | – | Leaf Blower | – | – | Leaf Blower | Edger | Leaf Blower, Edger | – | Leaf Blower |
| Dimensions | – | 8.23 × 40 × 7.36 inches | 37.4 × 10 × 5 inches | 7.09 × 72.4 × 8.9 inches | 11 × 44.9 × 7.52 inches | 36 × 9 × 14 inches | – | – | 56.7 × 17.7 × 41.3 inches | 12.9 × 9.37 × 35.8 inches |
| Weight | – | – | – | – | – | 1.52 pounds | – | – | 5.3 pounds | 15 pounds |
| Size | 16" | 13 inches | 320iL + 230iB Kit | 15" | – | – | 17" 40-Volt | 8" Edger (4.0Ah) | – | One Size |
| Color | green | Teal | Orange | Teal | Teal | Multicolor | Black | Green | Black and Orange | Clear |
| Model | – | XUX02SM1X4 | 970806701 | GRU01M1 | XUX02SM1X2 | RY40940VNM | Worx WG743, Worx WG163 | – | WG911 | DCKO975M1 |
You can evaluate line diameter and cutting swath across the best string trimmers with 4 0 ah to narrow your choices.
How to Choose the Right One
Match Voltage to Your Ecosystem
Check the voltage rating to ensure compatibility with your existing batteries. The EGO Power+ model operates at 56V, providing high power for larger yards. Makita tools use 18V or 40V systems, which suit users with existing Makita inventory. Ryobi and Greenworks also utilize 40V platforms. Selecting a tool that matches your current voltage system allows you to share a single 4.0 Ah battery across multiple devices. This reduces cost and simplifies storage for your garden equipment.
Consider Cutting Width for Efficiency
The cutting width determines how much ground you cover in a single pass. Wider decks, such as the 16-inch EGO Power+ or Husqvarna models, reduce the time needed for large areas. Narrower options, like the 12-inch WORX or 13-inch Makita, offer better maneuverability in tight spaces. Choose a wider trimmer if you prioritize speed and coverage. Opt for a narrower unit if you need precision around obstacles, fences, and delicate landscaping features.
Select Brushless Motor Technology
Brushless motors offer longer life and higher efficiency compared to brushed alternatives. Several Makita and Greenworks models feature brushless drives, which maintain power as the battery drains. This technology reduces heat buildup and wear on internal components. If you plan to use the trimmer frequently, a brushless motor provides consistent performance. Check the product attributes to confirm the motor type before purchasing.
Evaluate Multi-Tool Versatility
Some kits include attachments that transform the tool for different tasks. The Makita Couple Shaft system allows you to switch between trimming and hedging heads. Other bundles pair trimmers with leaf blowers or edgers. This versatility is ideal for users who want to minimize the number of separate tools they own. Verify the included equipment list to see if the kit offers the additional functions you need for complete yard maintenance.
Check Power Type and Source
All models in this guide are cordless, relying on battery power for mobility. Ensure the battery capacity meets your runtime needs. A 4.0 Ah battery provides a balance of weight and endurance for typical residential use. Verify the power type is listed as cordless or electric. This ensures you do not need an extension cord or fuel, allowing you to work anywhere in your yard without restriction or fumes.
Frequently asked questions
Which string trimmer has the widest cutting width with a 4.0 Ah battery?
The EGO Power+ and Husqvarna bundles both offer a 16-inch cutting width. This wider swath allows you to cover more ground in a single pass. It is ideal for users who prioritize speed and efficiency over compact maneuverability in tight spaces.
Are brushless motors better for string trimmers?
Yes, brushless motors generally offer longer life and higher efficiency. Several top picks, including the Makita 13-Inch and 15-Inch models, feature brushless technology. This design reduces maintenance needs and helps preserve battery charge during extended trimming sessions.
Can I use a 4.0 Ah battery with different voltage trimmers?
No, a 4.0 Ah battery is specific to one voltage system. You must match the battery to the tool, such as 56V for EGO or 18V for Makita. Using the correct voltage ensures proper power delivery and prevents damage to the motor or battery.
Which trimmer is best for users with existing Makita batteries?
The Makita 13-Inch Brushless Trimmer is designed for the 18V LXT ecosystem. It allows you to share your existing 4.0 Ah battery with other Makita tools. This versatility saves money and reduces the need to purchase additional batteries for different brands.
Do any kits include a leaf blower with the trimmer?
Several options bundle a leaf blower with the string trimmer. The Husqvarna 320iL and Ryobi 40V kits include both tools. This setup provides a complete yard care solution, allowing you to trim and clear debris with a single battery platform.
Is a 12-inch cutting width sufficient for most yards?
A 12-inch width is suitable for small to medium yards. The WORX and Greenworks models feature this compact size for precise work. It offers better maneuverability around obstacles and is easier to store than wider, more powerful 16-inch alternatives.
