Embroidery density converter

Convert a density value

Density value

The number exactly as your software, tutorial or design notes give it.

UnitSpacing in mmPoints (1 pt = 0.1 mm)Lines per inchLines per mmLines per cm

Changing the unit converts the value you entered.

Thread weight for the bands40 wt (standard)30 wt (thicker)

30 wt covers more, so its bands open by roughly 10 to 25 percent.

Convert

The units and how they convert

Every unit describes the same thing: how far apart neighboring stitches in a satin, or neighboring rows in a fill, sit. Two families run in opposite directions, which is the source of most density mix-ups.

The converter treats one point as 0.1 mm, so 4 points is 0.4 mm. That is the convention in many programs, but software conventions differ: some programs label density with their own scale or a different word, and a few express it as stitches or lines per unit length rather than spacing. If a value from your program looks wildly out of range here, check its manual or help file for what its density number means before you convert it.

Worked example

A tutorial says to set a satin to 4 points. That is 0.4 mm spacing, which is about 63.5 lines per inch (25.4 divided by 0.4), 2.5 lines per mm or 25 lines per cm. If your program asks for lines per inch, enter about 64. Going the other way, a fill set to 56 lines per inch is 25.4 divided by 56, about 0.45 mm or 4.5 points, at the light end of the usual tatami band.

Typical density bands

These are the starting points from our stitch density guide, for standard 40 wt polyester or rayon thread on a stable fabric with appropriate underlay. The converter marks where your value sits against each band. Treat them as the first test, not the answer.

For the medium satin band the converter accepts anything within 0.02 mm of the nominal value (0.38 to 0.42 mm for 40 wt) as "about 0.4". For 30 wt thread it opens the lower edge of each band by 10 percent and the upper edge by 25 percent, following the usual advice to open spacing by roughly 10 to 25 percent for the thicker thread. Narrow satins sit lighter than wide ones on purpose: short stitches barely spread, so packing them tightly just stacks thread into a hard ridge.

How to use the result

1. Translate, then compare. Convert the value from the tutorial, preset or design notes into the unit your own program uses, and enter that.
2. Check the band. "Denser than typical" is not wrong by itself (a wide satin or light thread on dark fabric may need it), but it is the first place to look if you see puckering, thread breaks or a stiff design.
3. Change one thing at a time. Adjust density in small steps, about 0.05 mm, and keep underlay, stabilizer and thread the same while you test.
4. Sew a density ladder on the real fabric, as described in stitch density, and keep the lightest setting that covers at normal viewing distance.

What the converter cannot tell you

• Density inside a stitch file you have resized. Scaling a stitch file (PES, DST, JEF and so on) without recalculation changes the spacing in proportion: shrink a 0.4 mm design by 20 percent and it becomes 0.32 mm. See resizing designs.
• Your fabric. Knits, towels, leather and light shirting each push the right value in a different direction. The fabric table on stitch density covers each one.
• Your thread brand. Real thickness varies between brands at the same nominal weight; see thread weights.
• Run time. Tighter spacing means more stitches. Put the new stitch count into the stitch time calculator to see what it costs per piece.

For a full tuning sequence when a design stitches badly, follow the Stitch-Out Tuning Method.