For the edges a robotic mower can't reach
Here's how the top-reviewed 2026 cordless string trimmers compare on motor power, line-feed system, and price.
Compare the top string trimmersQuick answer: Our top pick for cordless string trimmer is the EGO POWER+ ST1623T 16" LINE IQ String Trimmer (Best Overall). If you're looking for best heavy-duty, the Milwaukee M18 FUEL Dual-Battery String Trimmer is a strong alternative.
A robotic mower is built to stay a few inches back from fences, flower beds, and trees, both to protect its blades and to avoid clipping anything it shouldn't — which leaves a border of longer grass around the whole yard that only a trimmer reaches.
String trimmers split mainly by how they feed line: auto-sensing systems like EGO's LINE IQ keep a consistent cutting width without you thinking about it, while basic bump-feed trimmers need a manual tap against the ground to release more line. The other main split is power tier — homeowner-focused trimmers handle regular lawn edges fine, while pro-grade models like the Milwaukee M18 FUEL are built to also chew through thicker weeds and light brush.
| Product | Best For | Price | Rating |
|---|---|---|---|
| EGO POWER+ ST1623T 16" LINE IQ String Trimmer | Best Overall | $299 - $329 | 4.5/5 |
| Milwaukee M18 FUEL Dual-Battery String Trimmer | Best Heavy-Duty | $449 - $499 | 4.6/5 |
| RYOBI RY40290 40V HP Brushless Carbon Fiber String Trimmer | Best Value | $249 - $259 | 4.5/5 |
| RYOBI RY40250 40V Expand-It String Trimmer | Best Budget | $169 - $179 | 4.3/5 |
A 56V trimmer with auto-sensing LINE IQ line feed and POWERLOAD automatic line winding, built around a carbon fiber shaft rated as the strongest in this comparison and backed by a lifetime shaft warranty.
A dual-battery, three-speed brushless trimmer that reviewers rank among the strongest-cutting battery trimmers available, built more like a professional tool than a homeowner one.
A carbon fiber-shaft, attachment-capable trimmer that comes with a 4.0Ah battery and charger included, delivering over 70 minutes of runtime at a price well below the premium picks here.
An entry-level 40V trimmer with a 15-inch cutting swath and a 4.0Ah battery/charger included, aimed at buyers who want a reliable cordless trimmer without paying for extras they won't use.
The EGO ST1623T's auto-sensing LINE IQ and POWERLOAD system need almost no hands-on line management.
The Milwaukee M18 FUEL has the strongest cutting performance in this comparison.
The RY40290 shares a battery platform with the rest of Ryobi's 40V HP lineup.
The Ryobi RY40250 is the cheapest way into a cordless trimmer here, battery and charger included.