Resizing Embroidery Designs: the 15% Density Rule
Why scaling a PES or DST file is not like scaling a photo — what happens to stitch density, and how far you can safely push it.
A resize keeps every stitch
Machine embroidery files are lists of needle positions, not pictures. Scaling a design to 130% stretches the gaps between stitches by 30% — the thread count does not change. That is why resizing is free and instant, but only safe inside a limited range.
The 15% rule of thumb
The community consensus — confirmed by machine manuals and digitizers — is to stay within ±15% of the original size. Below 85%, stitches pile up: thread breaks, needles bend, bird-nests form under the fabric. Above 115%, fill areas look sparse and the fabric shows through. Beyond roughly ±30%, re-digitize instead.
What happens at the extremes
Oversized satin stitches gape and no longer cover the fabric; undersized lettering closes up into blobs. Watch the fill areas and any small text first — they show density problems before outlines do. Test-sew a small corner at the new scale before committing the whole garment.
Hoop sizes and fitting
Common home-machine hoops: 4×4 in (100×100 mm), 5×7 in (130×180), 6×10 in (160×260) and 8×8 in (200×200). When you scale to fit a hoop, the design must fit both dimensions — the limiting factor is the tighter one, and the fit is centred without rotation.
Resize without uploading
The Embroidery resizer resizes PES (Brother/Babylock) and DST (Tajima) files entirely in your browser: it warns at the ±15% thresholds, shows the density change and downloads the file in your original format with colours preserved.