20+ years in sewing threadThread consumption calculator
Work out how much sewing thread your order needs. Pick a garment, check the seams, and get metres per piece and the number of cones for the whole order.
1Choose your product
2Check the seams
| Operation | Stitch type | Length | Thread (m) |
|---|
3Order details
How the calculation works
Every stitch type uses a fixed amount of thread for each metre of seam. This is called the consumption ratio. The calculator multiplies each seam length by its ratio, adjusts for stitch density, fabric weight and garment size, adds the operations together, then adds wastage for thread changes, breaks and cone ends.
| Stitch type | Thread per 1 m of seam | Typical use |
|---|---|---|
| 301 Lockstitch | 2.5 m | Topstitching, workwear, jackets, hems on towels and bed linen |
| 401 Chainstitch | 5.5 m | Denim and workwear seams |
| 406 Coverstitch | 18 m | Hems and topstitch on knitwear |
| 504 Overlock, 3 thread | 14 m | Edges on knits, towels and bed linen |
| 514 Overlock, 4 thread | 18 m | Knitwear seams |
| 516 Safety stitch | 20 m | Woven seams with overlock |
| 605 Flatlock, 5 thread | 25 m | Decorative seams on sportswear and hoodies |
Needle thread and looper or bobbin thread are shown separately, because many factories run a heavier thread in the needle and a finer one in the looper.
Common questions
How is sewing thread consumption calculated?
Each stitch type uses a fixed multiple of the seam length, called the consumption ratio. For example 301 lockstitch uses about 2.5 m of thread per metre of seam, 401 chainstitch about 5.5 m and 514 four-thread overlock about 18 m. Multiply each seam length by its ratio, add the operations together and add wastage, usually 10 to 15%.
How accurate is the calculator?
It gives a planning estimate, usually within 10 to 15% of actual use. Stitch density, fabric thickness and seam construction change the result, so check it against a sewn sample before placing a large order.
How many cones do I need for my order?
The calculator divides the total thread for your order, including wastage, by the length of thread on each cone. It shows needle thread and looper or bobbin thread separately, because many factories use a different thread size for each.
Which thread should I use for denim, knitwear and workwear?
Denim and workwear usually use PolyCore thread, Tex 60 to 105 for needle seams. Knitwear usually uses spun polyester 40/2 or 50/2 on overlock and coverstitch machines. Home textiles such as towels and bed linen usually use spun polyester 20/2 to 40/2.
Need help choosing a thread size? See our PolyCore and spun polyester threads, or contact us.