How To Buy The Right Amount Of Weed Eater String

How Much Weed Eater String Do I Need

Weed eater string length is just one feature that gardeners should consider when shopping for replacement weed eater strings. Some say it isn’t as important as width or the shape of the line (round, square, spiral, etc) but length determines how much cutting you can get done in a single morning or afternoon.

Stopping to re-spool a weed eater can take an hour or longer (depending on the model) so the last thing you want is to run dry prematurely.

I’ve worked on lots of different landscaping jobs and I’m going to share some advice on how to buy the right amount of weed eater string. This article discusses, specifically, how to choose the right length of line for your yard work whether it involves overgrown grass, tough weeds or hills and slopes.

How Much Weed Eater String Do I Need

For a relatively small yard with no or few stubborn features, 100ft of weed eater string is usually enough. If you’re tackling a medium to large-sized yard with tall grass and ample weeds, 140ft of string should get the job done.

Very big gardens with a whole lot of lawn and lots of overgrown grass probably need around 315ft of weed eater string. Anything upwards of 300ft is a really long trimmer line. It’s unlikely you’ll need more than this unless you’re working on complex commercial projects.

But just in case you are, you can buy strings over 600ft in length as well. I don’t recommend buying this much line unless you’re landscaping over a huge area with a lot of thick, dense brush and foliage. If you bought this much string for light to medium duty work, you’d barely need to use any.

How Long Should Trimmer Line Be

The average length of trimmer line needed for a small to medium size yard based upon total volume being trimmed, type of terrain whether flat or sloped, the number of edges and obstacles like fences, trees and plant beds is 100ft to 150ft.

There is no definitive answer because all outdoor spaces are different. To choose the right amount for your project, consider its size and the toughness of the material you’ll need to cut through. A modest yard with a tame lawn and no slopes or weedy patches requires less line than the same sized yard with dense weeds and tall grass.

Always check the manufacturer’s instructions for your weed eater before buying a new spool. Smaller devices may not give you the option to use a large volume of line.

Similarly, some heavy-duty weed eaters might only take very large spools because they’re designed for commercial landscaping work. Always check your device’s specifications before buying new equipment or accessories.

Commercially available weed eater strings start at 30ft and extend to as long as 700ft or more for heavy-duty tools.

Weed Eater String Lengths Explained

  • 30ft – best for spot jobs and targeted trimming in small yards
  • 100ft – best for relatively small yards with no or few features/obstacles
  • 140ft – best for medium to large yards with tall grass and stubborn weeds
  • 300ft – best for large yards with multiple features/obstacles
  • 315ft+ – best for very large, overgrown yards or commercial landscaping

These estimations are just a rough guide. The best way to know for sure is to get familiar with your weed eater. If your neighbor is telling you there’s not enough string but you regularly stretch a spool out for two seasons, trust in what you know.

It’s not always a question of square footage. Small, dense yards go through string fast when they’re rife with shrubs, dips and stony patches. You should also account for the number of passes you’ll need before your grass looks presentable.

Weed eaters aren’t lawnmowers, so they’re not designed to cut at ground level, but it still might take two or even three passes before all of the grass is a uniform height.

Longer vs Shorter Length String

The worst thing that’s likely to happen if you use the wrong amount of string is you’ll run out of line mid-way and have to stop to add more. Or you’ll overestimate your needs and end up with enough weed eater string to last five seasons. Both scenarios can be frustrating but they’re hardly persistent problems.

Fortunately, most weed eaters have designs that make it obvious when a spool won’t fit because a string’s length is too long or short. It’s difficult to cause damage to the device itself just by making a less-than-perfect choice.

Though it’s worth remembering very thick strings need extra space for spooling. If you’re planning to use a very, very long weed eater line, consider how wide it’ll need to be to fit. The lengthier the string, the more you may need to compromise on its thickness.

One final factor to think about is the additional power needed to feed a very long trimmer string. Length does affect a device’s RPM because more revolutions mean more energy consumption. In most cases, the difference is negligible but eco-conscious homeowners and those on a tight budget might want to consider this.

If you’re stuck using a battery-powered weed eater in a fairly large garden (not the ideal combination), think about how to get the right balance between string length and power efficiency. Is it more important you don’t run out of wire or that you complete the job on one battery charge?

Shorter String Length


  • Uses less power (fewer RPMs)
  • Great for spot trims and small, simple yards


  • May need to be replaced 1-2 times in a large yard
  • Lightweight (easier to carry the weed eater)

Longer String Length


  • Can trim very large areas without stopping
  • May not be compatible with some lightweight devices


  • Uses more power (extra RPMs)
  • Adds extra weight to a weed eater

How Much Weed Eater String Do I Need

Here are some details to consider before buying a new weed eater string:

  • Your Weed Eater’s Specs (for compatibility)
  • Total size of the yard/trimming area
  • Number of features/obstacles in the yard/area
  • Toughness of the materials (grass, weeds, brushes, etc)
  • Battery power vs line length (if relevant)
  • Thickness vs line length (for compatibility)
  • Noise made by some longer strings (more vibrations)
  • The need for additional edging/tapering
  • Private or commercial landscaping

Best Overall Trimmer Line: LoNoiz Spiral Twist Line

My top choice has to be a LoNoiz spiral twist grass trimmer line. It’s designed to tackle the trickiest of weeds with ease and decimates grass and brush both near and around hard surfaces.

I’ve used this brand a lot and even its long lines (300 ft+) are surprisingly quiet. LoNoiz promises noise reduction capabilities and it does deliver which is something a lot of longer strings cannot do.

The vibrations are noticeably smoother, so your weed eater isn’t rattling around and betraying your 5am obsession with that tuft of grass you overlooked last week (okay, maybe that’s just me).

LoNoiz string is highly durable and offers great value for money. LoNoiz’s trimmer string is suited to gardeners who require a sturdy, long-lasting line or want to cut their own windless ‘pre-cut’ lines.

It’s a fantastic choice for general clean-up jobs, larger weeds and brushes, as well as fitting windless alternative trimmer heads.

Helpful Tips For Making Your Weed Eater String Last Longer

  • Hold and carry the weed eater correctly
  • Use a string length that’s suitable for your project
  • Use a heavy-duty string to tackle tough terrain
  • Keep the string parallel to the ground for a smooth feed
  • Learn to listen to the string hammer (for optimal re-spooling)
  • Do not overfeed the trimmer line
  • Invest in trustworthy, high-quality brands

Final Thoughts

As with most things, experience makes this type of decision much easier. When I need to purchase new gardening equipment, I like to read online guides, blogs and recommendations because there’s always somebody more experienced out there who’s keen to share their knowledge.

Though you will find, in time, you can just look at an outdoor space and its features and make a pretty good guess as to what type of string is best.

There are other considerations, of course. Thickness and the shape of a weed eater string affect its performance in some subtle and major ways. The secret to having the best, most efficient landscaping tools on the block is taking some time to figure out how all of these characteristics combine.

Drew Thomas

My name is Drew Thomas and I’m the creator of Fun In the Yard, your one stop site for all your outdoor games, sports, party activities, outdoor gear, and lawn & gardening tips.

Related Posts