String Trimmer Line Sizes Explained

String Trimmers8 min read

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The short answer

Use 0.065-inch line for light grass, 0.080-inch for normal lawn edges and weeds, 0.095-inch for thick weeds and brush, and 0.105-inch for heavy clearing. Round line is quietest, twisted and serrated lines cut cleaner in thick growth but wear faster.

StandardTypically $12 – $20

0.080-Inch Trimmer Line Bulk Spool

The standard diameter for normal lawn grass and light weeds.

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Line diameter is the single easiest way to improve or ruin a trimmer's performance. Too thin and the line melts against fence posts; too thick and the motor labors, the head feeds poorly and you waste money on line the tool cannot use.

DiameterBest forTypical use
0.065 inLight grass, detail workSmall yards, flower-bed edges
0.080 inNormal lawn grass, light weedsMost suburban trimming
0.095 inThick weeds, fescue, fence linesHeavy residential use
0.105 inBrush, saplings, thick stemsClearing and pro use
Line size by job

Line Shapes Matter Too

  • Round line: cheapest, quietest, wears slowly. Best for normal grass.
  • Twisted line: cuts cleaner, reduces drag, throws less debris. Good for weeds and edges.
  • Serrated / saw-tooth line: aggressive cutting on woody stems. Wears fast and is noisy.
  • Square / multi-sided line: bites into thick growth but can vibrate more than round.

Can Your Trimmer Handle the Line?

Check the head capacity, not just the motor. A 20V homeowner trimmer may list 0.080 as the max line. Forcing 0.095 through it strains the motor and the bump-feed mechanism. Most 40V and 56V trimmers handle 0.095 comfortably; 0.105 usually needs a pro head or a gas machine.

How to Reload Line Faster

  1. 1Cut a 10-foot length of line and find the center.
  2. 2Thread the two ends through the eyelets on opposite sides of the head.
  3. 3Wind both spools in the direction shown by the arrow on the head.
  4. 4Leave 6 inches sticking out; the trimmer will pull them to the right length on startup.

Frequently Asked Questions

What size line does an EGO string trimmer use?
Most EGO trimmers ship with 0.095 line and accept up to 0.095. Check the head label, but 0.080–0.095 is the normal range.
Is thicker trimmer line always better?
No. Thicker line cuts better in weeds but loads the motor more, feeds poorly in light heads and costs more. Match the line to the job.
Why does my trimmer line keep melting?
Melting usually means the line is too thin for the load, you are moving too slowly, or the line is rubbing concrete and fences. Try a thicker line or a tougher shape.
How long should trimmer line last?
A spool can last one season of normal use or one afternoon of fence-line abuse. Buy line by the bulk roll once you know the diameter your head likes.

The Gear We’d Buy

Everything referenced in this guide, in one place.

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Key Takeaways

  • 0.080 inch is the right diameter for most suburban trimming.
  • Move to 0.095 inch for thick weeds and fence lines.
  • Match line diameter to the trimmer head capacity, not just the motor.
  • Twisted line cuts cleaner; round line lasts longer and is quieter.

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Standard

0.080-Inch Trimmer Line Bulk Spool