Sewing needle sizes: NM to Singer
Two numbering systems for the same needle. One is a measurement, the other is a convention — and only one of them tells you anything about the fabric.
What does the needle size 80/12 mean?
The first number is the metric size, NM 80, which is the blade diameter in hundredths of a millimetre, so exactly 0.80 mm. The second is the Singer or US equivalent, 12. Both describe the same needle, and 80/12 differs from 90/14 by only a tenth of a millimetre.
How do I choose a needle size for my fabric?
Match the needle to fabric weight rather than to habit. Fine wovens take 60/8 to 70/10, everyday shirting and jersey take 75/11 to 90/14, and denim or canvas needs 100/16 to 110/18. Too heavy a needle leaves visible holes; too fine a one deflects and skips stitches.
Needle size conversion table
The metric designation is the actual needle diameter in hundredths of a millimetre, measured above the scarf. Packaging usually prints both systems, as in 80/12.
| Metric NM | Singer / US | Blade diameter | Typical fabric |
|---|---|---|---|
| 60 | 8 | 0.60 mm | Chiffon, fine silk, voile |
| 65 | 9 | 0.65 mm | Fine wovens, lightweight lining |
| 70 | 10 | 0.70 mm | Poplin, fine shirting |
| 75 | 11 | 0.75 mm | Light cotton, jersey |
| 80 | 12 | 0.80 mm | Everyday shirting, medium jersey |
| 90 | 14 | 0.90 mm | Medium woven, twill, light denim |
| 100 | 16 | 1.00 mm | Denim, canvas, heavy twill |
| 110 | 18 | 1.10 mm | Heavy denim, upholstery weight |
| 120 | 19 | 1.20 mm | Webbing, heavy canvas |
| 125 | 20 | 1.25 mm | Very heavy woven |
| 130 | 21 | 1.30 mm | Leather, heavy industrial |
Reading the number
NM is the diameter times one hundred. An NM 100 needle is 1.00 mm across; an NM 60 is 0.60 mm. The Singer scale runs 8 to 21 over the same range and carries no unit — it is a convention, not a measurement.
The two systems are not interchangeable mid-range. There is no Singer number between 12 and 14, so NM 85 has no exact US equivalent and packaging rounds it.
What goes wrong on the floor
- Needle too heavy — visible perforation along the seam line, worst on fine woven and coated fabric
- Needle too fine — the blade deflects against a dense weave and the hook misses the loop, producing skipped stitches
- Blunt point on knit — a sharp point cuts the loop instead of parting it, and the damage shows as a ladder after the first wash
Needle breakage and skipped stitches are recorded as machine-level defects, which is how a pattern gets spotted before a whole lot is affected. See shop floor control for how a defect is attributed to a machine and operator, and stitch and seam types for the stitch each machine forms.
Copy this attribution
Scan ERP — Sewing Needle Size Chart — NM to Singer Conversion. https://scanerp.pro/needle-sizes/
Sizes follow the manufacturers’ standard convention (NM = blade diameter × 100); every row in the table satisfies that relationship. Check your needle supplier’s catalogue for specialist points. Last reviewed 29 September 2026.