The Nylon Thread Buying Guide helps customers get the right thread for their needs. Our approach is to decide if nylon is the right thread for the job, identify which sizes (thicknesses) should be used, and finally pick the color and spool size that works. We have nylon thread in eleven sizes, over 100 colors, and putups ranging from small spools priced around $10 to discounted cases.
Nylon Thread Uses - Nylon is a general purpose thread designed for applications that require a strong, inexpensive, easy sewing thread with a glossy finish. It is the first choice for upholstery, leatherwork, auto interiors, banners and flags, sports gear, dog collars, horse saddles and tack, knife sheaths, gun holsters, fishing lures, and brief cases. Lighter weight sizes are often used for sewing garments made from nylon or other shiny fabrics. See the
Nylon Thread Uses / Size Ranges for details.
There are times when other threads work better than nylon:
Outdoor applications with prolonged sunlight exposure. For example, nylon thread is a great choice for sewing indoor upholstery, and canvas drop cloths used by house painters. It should not be used for outdoor furniture and sewing canvas sails, awnings, tarpaulins. In these cases
polyester thread or UVR rated nylon thread are better choices.
Fire retardant garments and gear - Nylon thread yellows at 300F, sticks at 445F and melts at 500F. First responder garments and gear and some high temperature conveyer belts require much more fire retardance.
.Kevlar and Fire Retardant in these situations. They are heat resistant to 700F or more and do not melt
Critical strength requirements - Nylon is strong but Kevlar Thread is about twice as strong. For example, size 92 nylon has a 15 pound tensile strength; the same size Kevlar has a 30 pound tensile strength. Kevlar's downside is that it costs about five times more than nylon and only available in yellow. Consider using heavier weight nylon or double-stitching to meet strength requirements.
Cotton-like look - Our nylon thread has a smooth, glossy, shiny finish that does not go well with garments that need a soft, fuzzy, cotton-like look. Cotton, spun polyester and nylon thread, and fuzzy nylon are better and less expensive choices. We do not sell these products.
Nylon Thread Size -
Thread size refers to the thread's approximate thickness. Thread is soft and spongy and its thickness cannot be accurately measured with calipers. The Commercial and Tex sizes on our site measure the weight of a fixed length of thread. For example, a 1,000 meters of Tex 70 weighs 70 grams. Having said this, the military includes thread thickness in their specifications and we include them in our
Nylon Thread Specifications.
Thread size is important because it affects so many things:
When thread size increases...
When thread size increases...
Sewing machine size
Sewing heat and friction
Yards per pound
The material that you are sewing costs far more than the thread. In most cases (parachutes excepted) it is better for the thread to break than to have the stitches pull through the fabric. This means that the weight of the fabric, in ounces per square yard, is the best way to determine thread size. Here are size recommendations for fabric and leather.
Fabric Ounces Per Yard
Thread Size Range
Leather Ounces Per Yard
Thread Size Range
2 to 6 Ounces
15 to 33
1 to 8 Ounces
46 to 207
6 to 8 Ounces
33 to 46
8 to 12 Ounces
138 to 277
8 to 10 Ounces
46 to 69
12 to 16 Ounces
207 to 346
10 to 12 Ounces
69 to 92
207 to 346
12 to 14 Ounces
92 to 207
There other things to consider. You may use a thinner thread because your machine cannot handle a heavier thread. Or, you may choose a thicker thread because you want stitches to stand out.
Bonded or soft? - Bonded means that a thread has a coating that reduces needle heat and fraying. It makes thread stiffer and about 5% thicker than soft thread that does not have a coating. The choice between bonded and soft depends on how the thread is going to be used and thread thickness. Here are our recommendations:
Machine sewing lightweight
thread sizes 15 to 46
Lightweight thread sizes generate little needle heat and are unlikely to fray. Bonded and soft thread work equally well.
Machine sewing thread sizes 69 and higher
Bonded thread is strongly recommended
It does not matter if you use bonded or soft thread.
Wrapping and gluing
Soft thread is preferred because bonded thread often repels glues and adhesives. You can soak a bonded thread in alcohol to remove the bonding.
Other non-sewing applications such as hanging and reinforcing
Finish does not matter in most cases. Bonded thread is better if it is going through a narrow tube.
Spool Sizes -
We sell most of our nylon thread in 2 Ounce, 4 Ounce, and 16 Ounce (1 Pound) spool sizes or putups. The smaller putups cost more per ounce than the larger ones. But, they are a better choice for one-time jobs, casual sewers, people who need a stash of many colors, and experimenters.
Nylon thread is sold by weight (ounces, pounds) - not yards. This is because the number of yards-per-pound decreases as thread thickness increases. Selling by weight means prices for a given size spool are about the same across most thread sizes..
Industry norms allow nylon thread spool weights to vary by plus/minus 10% from the stated nominal weight. This means that customers get slightly less or slightly more thread than the nominal weight shown on our site. The table on the right shows our nominal weights and the thread-weight range ( including the spool's weight ) for various sizes. When spools fall within these ranges we do not charge for overages or refund underages. Here are the weight ranges we use:
Spool base width and height vary with the putup:
2 and 4 Oz
12 and 16 Oz
Nylon thread stretches about 25% before it breaks. This means that 10 yards of nylon thread will be 12.5 yards when it snaps. This stretchiness is a good thing in most cases. It allows the seams to expand and contract with the material and avoids puckering and breakage. Nylon's stretchiness may not be desirable in some hanging, reinforcing, or wrapping applications. When this is so, consider less stretchy threads such as cotton, spun polyester, or Kevlar.
Twist - Most of the nylon thread on our site
is left twist (also called Z-twist) because that is what single-needle machines made for the U.S. use. We have a few, clearly marked, right twist (also called S-twist) thread for double-needle machines. A thread's twist makes no difference when it comes to hand-sewing and non-sewing applications.
Monocord Nylon Thread - Regular nylon thread has two or more plies that are twisted together and bonded. Monocord nylon thread is made from hair-thin nylon filaments that are bonded together in a single ply. This gives the thread a smooth, flat, ribbon-like texture and makes it 10% to 14% stronger than regular nylon. Its single ply runs smoother through needles reducing needle change frequency. Since it has no twist, it can be used with both needles in a double-needle machine and for bi-directional sewing. Machine retensioning is usually required when switching between regular and monocord thread.
Use monocord nylon any place that regular nylon is used. It is the first choice for low profile stitching where stitches are inconspicuously buried in the fabric or leather. Burying stitches makes them less susceptible to abrasion, wear, and tear. This is a big advantage in furniture upholstery, automobile seats, climbing gear, and pet accessories.
Some of our monocord is labeled UVR. This means that has sunlight (UV) resistance similar to polyester.
Monocord nylon thread has the same vibrant color range as regular nylon. It is not transparent like monofilament.
Inches - decimal
Inches - thousandths
2 Ounce Spool
4 Ounce Spool
8 Ounce Spool
12 Ounce Spool
16 Ounce Spool
Thread Size and Machine Type - As thread size increases, a more powerful machine is needed to push the thread through the material.