Best String Trimmers 2026 ▷ Battery, Gas & Electric Buying Guide

String Trimmer Types: Battery, Gas, and Corded Electric

Battery String Trimmers

Battery string trimmers have largely displaced gas for residential use in the same way battery lawn mowers have. Modern 56V (EGO) and 40V (RYOBI, Greenworks) brushless trimmers match gas torque on normal residential grass and weeds. The key feature that separates good battery trimmers from frustrating ones is the line feed system: auto-feed (EGO POWERLOAD) or REEL-EASY (RYOBI) are more reliable than traditional bump-feed heads, which require periodic manual re-threading.

Gas String Trimmers

Gas string trimmers remain the right tool for: large rural properties with extensive rough trimming needs, very heavy vegetation (thick brambles, woody stems, tall grass over 12 inches), commercial landscaping requiring 4+ hours daily, and properties too remote for practical battery charging. The Husqvarna 128LD at 28cc delivers sustained torque that battery trimmers in its price tier cannot match under heavy-load conditions. 2-stroke gas trimmers require fuel mixing; 4-stroke models (Honda, Husqvarna 4-stroke) run on straight gasoline but are heavier.

Corded Electric String Trimmers

Corded electric trimmers are the most affordable entry point: an 8–12 amp model costs $30–$80 and never needs a battery or fuel. For small urban yards where an outlet is within 50 feet of all trimming areas, a corded trimmer handles light edging and trim work perfectly. The cord management is the only real friction — on a simple rectangular lot it's straightforward; on a complex yard with many obstacles it becomes genuinely annoying. The Sun Joe or RYOBI corded models in this range are adequate for occasional light residential use.

Buying Guide: Cutting Width, Line Diameter, and Shaft Type

Cutting Width

Cutting width determines how much area you cover per sweep. The practical range for residential trimming is 12–17 inches. 12–13 inches is precise and easy to control around delicate plants, fence posts, and garden statuary — best for detail work and small lots. 15–16 inches is the most versatile residential width — efficient enough to trim open areas quickly, precise enough for careful work around obstacles. 17+ inches is semi-professional territory, where covering more ground per pass is the priority over precision.

Line Diameter and Shape

Standard residential trimming uses 0.065–0.080 inch round line for light to medium grass. For tougher conditions — thicker weeds, heavy seasonal growth in wet climates — 0.080–0.095 inch handles the cutting load without stalling a brushless 56V motor. Above 0.095 inch is for semi-professional and gas-powered equipment. Line shape matters: round monofilament lasts longest; twisted, serrated, and star-shaped profiles cut more aggressively but wear 30–50% faster and cost more per spool. For normal maintenance trimming, round 0.080–0.095 inch line on a quality battery trimmer is the most practical combination.

Straight vs Curved Shaft

Straight shaft trimmers: better reach under decks, raised shrubs, and fences; more appropriate for taller users (6 ft+); required for Expand-It attachments that convert the trimmer to an edger, cultivator, or pruner. More comfortable for sustained use with proper posture. Curved shaft trimmers: more compact, lighter, slightly easier to maneuver in tight spaces; better suited for shorter users. Curved shafts use a flexible cable drive rather than a rigid shaft — this limits the power that can be transmitted, making curved shaft models slightly less powerful under heavy load than equivalent straight shaft models. For a standard residential trimmer, either works; power users and anyone using attachments should choose straight shaft.

Top String Trimmer Picks for 2026

For detailed comparisons:

• Best Battery String Trimmers 2026 — EGO ST1521S, RYOBI RY40250, CRAFTSMAN CMCST900D1
• Best Gas String Trimmers 2026 — Husqvarna 128LD and gas alternatives

String Trimmer Line: Types, Sizes, and How to Replace It

The trimmer line is the working end of the tool — it wears, breaks, and needs replacement. Understanding line diameter, shape, and replacement procedures separates frustration from efficient trimming.

Line Diameter Selection Guide

String trimmer line comes in standard diameters, each designed for specific cutting loads. Using the wrong diameter creates problems: line too thin burns out rapidly under load; line too thick overloads the motor and causes premature failure.

0.065-inch diameter: Appropriate for light residential trimming on normal grass, edging, and maintenance work. This is the standard diameter for most 20V battery trimmers (CRAFTSMAN, entry-level RYOBI). Runtime is excellent because the motor runs efficiently at low load. Suitable for weekly maintenance on small to medium lots (under 5,000 sq ft).

0.080-inch diameter: The middle ground for 40V battery trimmers (RYOBI 40V ONE+, Greenworks 40V). Handles heavier grass, medium weeds, and denser growth without stalling the motor. Recommended for properties where the weekly trimming session includes areas of thick weeds or seasonal overgrowth. This diameter is the most versatile for residential use.

0.095-inch diameter and above: Required for 56V battery trimmers (EGO) and all gas trimmers. At this thickness, the line cuts with aggressive force suitable for woody stems up to 1/2 inch diameter, thick brush, and demanding conditions. Never exceed the maximum line diameter specified in your trimmer's manual — the gearbox and motor are engineered for specific loads. Using 0.095-inch line on a 20V trimmer will overheat and burn out the motor within a season.

Line Cross-Section: Round vs Twisted vs Serrated

Beyond diameter, line shape affects cutting performance and durability. The three main profiles are:

Round monofilament: The standard and most economical option. Round line lasts the longest (typically 4–6 weeks of weekly use on a suburban lot) because the entire circumference of the line participates in cutting. It produces a clean edge on grass without aggressive shredding. Most common on battery trimmers and budget gas models.

Twisted or spiral line: Creates an aggressive cutting action by concentrating force on twisted edges. This line cuts thicker weeds and woody stems more effectively but wears 30–50% faster than round line. The trade-off: you reload every 2–3 weeks instead of 4–6, but the cutting performance on tough vegetation is noticeably superior. Cost per spool is typically 20–30% higher.

Star-shaped or serrated line: Provides the most aggressive cutting action of any profile, with multiple cutting edges per cross-section. Perfect for clearing overgrown areas before mowing season, but the durability is poor — expect 1–2 weeks of active use on heavy vegetation. Star line is specialty equipment; if you find yourself using it routinely, a gas trimmer with higher torque is a better investment than buying expensive specialty line repeatedly.

For standard residential maintenance, round 0.080–0.095 inch line provides the best balance of longevity and cutting effectiveness. Reserve twisted or serrated profiles for seasonal heavy-duty projects or properties with persistent thick weeds.

How to Replace String Trimmer Line

Line replacement method depends on your trimmer's feed system. There are three common designs:

Bump-feed heads (traditional): A spool of line sits inside the trimmer head housing. To advance line, you tap the head against the ground while the trimmer is running, and a mechanism inside releases more line. To reload when the spool empties: (1) stop the trimmer and let it cool; (2) remove the spool cap (usually by twisting counter-clockwise); (3) pull out the empty spool; (4) wind new line onto the spool following the directional arrows molded into the spool hub, leaving 3–4 inches free on each side for the exit guides; (5) thread the free ends through the exit guides and reinstall the spool. This process takes 5–10 minutes and is fiddly — the most common complaint about string trimmers. Many users find it frustrating enough to consider upgrading.

REEL-EASY or manual feed heads (RYOBI design): A simplified bump-feed system where you can reload without removing the spool cap. Pull a release tab, and the dual-exit spool allows you to pull pre-cut line segments directly by hand, then press to secure. Reloading takes 60–90 seconds instead of 5–10 minutes. This is a meaningful improvement over traditional bump-feed and is now standard on RYOBI and many entry-level battery trimmers.

Auto-feed systems (EGO POWERLOAD): The most seamless experience. Insert a pre-cut straight line segment into the head opening, press a button while the trimmer is running, and the motor winds it onto the spool in 5–10 seconds with no manual re-threading required. When the line wears short during use, bump the head against the ground as normal; when the spool empties, reload another segment. No fiddly winding, no off-center spooling. The convenience is worth the premium for users who trim weekly or find manual re-threading genuinely maddening.

Safety Gear and Protective Equipment

String trimmers operate the cutting line at 7,000–10,000 RPM. At this speed, the line impacts with enough force to cause injury. Projectile risk is real: the spinning line can throw small stones, wire fragments, and hard debris at eye level. Lacerations from direct contact with the line are severe.

Eye protection: Non-negotiable. A basic safety glasses or full face shield minimizes debris impact. Impact-rated glasses (ANSI Z87.1 certified) are inexpensive and widely available. On windy days or when trimming in areas with loose gravel, a full face shield provides better coverage than glasses alone.

Hearing protection: Gas trimmers operate at 90+ decibels — sustained exposure causes hearing damage. Even battery trimmers at 85+ dB warrant hearing protection for regular use. Simple foam earplugs or earmuff-style hearing protectors are effective and inexpensive.

Leg and foot protection: Wear long pants to protect legs from line contact. A direct hit from the spinning line on bare legs causes deep lacerations. Closed-toe shoes or boots are essential; sandals or sneakers with exposed skin at the toe line create unnecessary risk.

Additional considerations: Keep the trimming area clear of bystanders and pets before starting. Maintain a 50-foot safety radius from any other person during operation. When trimming near hard surfaces (concrete, asphalt), allow clearance between the line tip and the pavement — contact with hard surfaces accelerates line wear and throws concrete chips.

String Trimming Technique

The most common mistake in string trimming is using too high a cutting head height, leaving a visible strip of uncut grass between the mower's cut and the trimmer's. Work with the cutting head at approximately the same height as the mowed lawn surface — the spinning line should be at or just slightly above the turf, creating a consistent finished height across the yard.

For edging along hard surfaces: tilt the trimmer to vertical (90 degrees) with the spinning head parallel to the pavement edge. Work with the left side of the rotation (the rotation throws debris away from you when the head is vertical) cutting into the edge. Keep the cutting head at a consistent height and move steadily forward — wavering speed creates uneven edges.

For trimming around trees: keep the cutting line from touching the tree bark. Contact between the spinning line and bark at 7,000+ RPM strips the cambium layer (the living tissue just under the bark), effectively girdling the tree if done repeatedly over seasons. This "weed whacker blight" kills more residential trees than most pests or diseases. Keep 3–4 inches of clearance between the spinning line and any tree trunk.

Feed the line frequently rather than waiting until the stub is too short to cut effectively. Trimming with a very short line puts more load on the motor and produces ragged cuts. A well-fed line at 3–4 inch length cuts cleanly with less motor stress.

Frequently Asked Questions

Frequently Asked Questions

What is the difference between a string trimmer and a weed eater?

They are the same tool — "string trimmer," "weed eater," "weed whacker," and "line trimmer" all refer to the same rotary cutting tool that uses a spinning monofilament line to cut grass and weeds. "Weed Eater" is actually a brand name (owned by Husqvarna) that became genericized as a common name for the tool category, similar to how "Band-Aid" became a generic term for adhesive bandages. The tool cuts by spinning a line at high speed (7,000–10,000 RPM) that severs vegetation on contact.

What cutting width do I need for a string trimmer?

For residential edging along sidewalks, driveways, and garden beds: 12–13 inches is sufficient and easy to control. For trimming around obstacles (trees, fence posts, raised beds) and light-coverage areas: 13–15 inches is the most versatile residential range. For trimming larger open areas where the trimmer supplements a mower: 15–17 inches covers more ground per pass. Commercial and semi-professional use: 17+ inches. The CRAFTSMAN CMCST900D1 at 13 inches and EGO ST1521S at 15 inches bracket the most common residential range — both work for edging and trimming, with the EGO covering more area per sweep.

What line diameter should I use in my string trimmer?

0.065–0.080 inch: appropriate for light grass, edging, and trim work in average residential lawns with normal grass growth. This is the standard diameter for most 20V–40V battery trimmers. 0.080–0.095 inch: for heavier grass, thicker weeds, and more demanding residential use. Required for most 56V battery and gas trimmers working through taller vegetation. 0.095–0.105 inch: semi-professional use, thick brush, and applications requiring maximum cutting resistance. Always check your trimmer's manual for the maximum recommended line diameter — using line that is too heavy overloads the motor and burns it out prematurely. Line cross-section shape also matters: round line lasts longest; twisted, star-shaped, and square profiles cut more aggressively but wear faster.

How do I feed more line on my string trimmer?

Most residential string trimmers use bump-feed heads: tap the head against the ground during operation to automatically advance more line. If the line stops advancing: check that the line is not tangled or fused in the spool (heat from high-speed contact with hard surfaces like concrete can weld the outer layers of the line together). If tangled: stop the trimmer, remove the spool cap, untangle or cut free the fused section, re-thread if necessary. Manual feed (REEL-EASY heads on RYOBI) allows pulling the line out by hand with the trimmer off. Auto-feed systems (POWERLOAD on EGO) use the motor to advance line automatically without bumping — the most convenient and least frustrating approach for users who find bump-feed frustrating.

Can I use a string trimmer as an edger?

Yes — most string trimmers can be rotated 90 degrees to use the trimmer head vertically as an edger, cutting along sidewalk and driveway edges. This technique works well for maintaining defined edges on existing straight lines. A dedicated edger produces cleaner, more vertical cuts and better-defined edges with less operator effort. For occasional edge maintenance on a normal residential yard, using the trimmer as an edger is practical. For formal lawn edges, particularly curved beds and garden borders, a dedicated lawn edger (or an Expand-It attachment on compatible RYOBI/CRAFTSMAN trimmers) produces superior results.