Fishing Line Strength Diameter Chart: Why Is It Important?

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As you grow your angling skills, the details of your rod and reel setup begin to matter more. At one point, you may have picked the cheapest fishing line you could find, attached it to your reel, tied it to your hook, and not even thought twice about it! 

However, as anglers gain more experience, it’s obvious that things like the fishing line are a crucial factor when fishing, in both the quality and the size of the fish you try to catch. 

In this article, I will show a fishing line diameter chart based on the average top brands of lines and provide some useful information on how this affects whether you should use the best braid, monofilament, or fluorocarbon line. 

Line Test*Monofilament DiameterFluorocarbon DiameterBraided Line Diameter
2LB.005in.005in.004in
4LB.008in.007in.006in
6LB.009in.009in.005in
8LB.010in.010in.007in
10LB.011in.011in.008in
12LB.013in.012in.009in
14LB.014in.013in.009in
17LB.015in.015in.010in
20LB.016in.016in.010in
30LB.020in.020in.012in
40LB.024in.022in.013in
50LB.028in.029in#.014in
60LB.030in.032in#.015in
Mono To Fluoro To Braid Line Diameter vs Line Strength Chart
  • The chart shows an average comparison of multiple manufacturers
  • * Line test is also known as the breaking strain
  • # Note that fluoro over 50lb is slightly larger in dia than mono

Why Is Fishing Line Diameter Important?

Trout and other fish species can be finicky, fishing with a lower-diameter line as possible is the best option

Fish are picky! If your line is too thick or is the wrong material, you may catch half the amount of fish that you should have.

You can use the wrong type of line meaning the fish won’t bite. Or, it’s very likely you may have used the perfect line type, but the test is wrong. 

What Is The Impact Of Using The Wrong Line Test?

  • Using too thick a line will likely shy away fish from your bait.
  • Using too thin a line can break when landing a large fish

Either way, it’s important to have a strong understanding of all types of fishing lines. Other than your bait, it’s the most important part of an angler’s fishing tackle! Especially, if you want to catch more fish and bigger fish! 

Comparing Fishing Line Diameter

The general rule is that braid is almost always thinner than both mono and fluorocarbon lines for the same strength test.

Fluoro and mono are very similar in their diameters versus their strength. You may find that most manufacturers of fluoro have around 5% – 10% less diameter than a mono line.

What Are The Advantages Of Thin Fishing Lines? 

  • The major difference (as we mentioned earlier) is that the fish will have less chance of seeing a thinner line than a thicker line. Which will create more bites and takes on your bait.
  • Another benefit is that you can spool far more line on a reel with a lower diameter line, therefore braid (being a lower diameter) will allow you to fill at least 30% more line on your reel. 
  • Using thinner lines when fishing during the colder months will get you more bites. The fish become warier and will eat only the best-presented baits.
  • Your bait or lures will flow more naturally in the water.
  • Finally, you will find it is always easier to cast further distances with thinner lines.

Final Thoughts

If you have read several of my articles on fishing lines you will know by now that there are lots of important aspects to understand in three main types of fishing line.

Other than cost, knot strength, stretch/memory, abrasion/shock resistance, etc, its line diameter is definitely one of the most forgotten about.

I hope this informative article was interesting and helped you understand the effects of line diameters and strength. Please check out my article on braid, mono, and fluoro lines compared here! which outlines all the benefits and negatives of each line.

Daniel Mooers