What is the DST file format?
The .dst file extension (Tajima CAM) is used by embroidery machines and software. Developed by Tajima (Tokai Industrial Sewing Machine Co.) in the 1980s, the Tajima embroidery format became the de facto universal interchange standard and is widely supported by embroidery machines and applications around the world.
A .dst file holds stitching instructions for an embroidery machine, such as trim, stop, color-change, and jump. The file also contains label metadata identifying the design.
.dst file structure
Each .dst file contains a header and a binary stitch body. The header opens with the ASCII signature LA: at byte offset 0, followed by the design label. It also records stitch count (ST:), color-change count (CO:), and design extents (+X:, -X:, +Y:, -Y:). The maximum length of the header is 512 bytes; however, 125 bytes is the most commonly used value in practice.
Each stitch record in the file body is 3 bytes long, encoding relative X/Y coordinates and a command flag - one byte longer than the 2-byte records used by many other embroidery formats such as .PES or .JEF. The coordinate unit is 0.1 mm, with a maximum jump of ±121 units (±12.1 mm) per axis per stitch step.
Note that .dst is also used by unrelated software (for example, AutoCAD drawing-set files), but in the embroidery context the LA: header signature distinguishes a genuine Tajima stitch file.
Security & safety
RISK: LOWA .dst is passive stitch data - it can't execute and is safe to open in embroidery software. The practical cautions are operational, not security: because plain DST carries no thread colors, always check the design's size, stitch count, and color sequence in a viewer before stitching to avoid wasting thread and fabric. When downloading 'free DST designs', stick to reputable marketplaces - some sites wrap downloads in adware installers or mislabel low-quality auto-digitized files. Scaling a stitch file (DST) up/down significantly without re-digitizing degrades quality, since the stitch density is fixed.
Format details
in a nutshellPrograms that open DST files
Windows4 apps
Embird Embroidery Software
Paid Open, edit, recolor, resize, and convert .dst; modular embroidery suite. (trial available) 
Embroidermodder
Open-source Free open-source embroidery file viewer/editor; opens and converts .dst. (development is intermittent - verify the current build).
Wilcom TrueSizer
Free Free Wilcom viewer: open the .dst to preview, resize, see stitch count, and convert to other embroidery formats. Best free desktop option.
Ink/Stitch (Inkscape)
Open-source Free Inkscape extension: open/preview a .dst and digitize new designs from vector art, then export DST/PES/etc. 
macOS2 apps
Convert It, Mac
Paid Mac embroidery conversion tool (BriTon Leap): open and convert .dst between machine formats.
Wilcom TrueSizer Web
Free Browser-based Wilcom viewer: upload the .dst to preview and convert without installing anything (works on Mac). 
Linux2 apps
Ink/Stitch (Inkscape)
Open-source Free: open Inkscape with Ink/Stitch to view/convert .dst and digitize designs.
libembroidery / Embroidermodder
Open-source Open-source library/tool to read and convert .dst on Linux.
Wilcom TrueSizer Web
Free Upload a .dst to preview in 3D and convert to PES/JEF/etc. in the browser - no install. Technical details
deep spec| Format class | Binary machine-embroidery stitch file (stitch coordinates + machine commands) |
| Developer | Tajima (Tokai Industrial Sewing Machine Co.) |
| Header size | 512 bytes ASCII header; 125 bytes is the most common value used in practice |
| Header signature | `LA:` ASCII string at byte offset 0 (design label field) |
| Stitch record size | 3 bytes per stitch record (vs. 2 bytes in many competing embroidery formats) |
| Coordinate unit | 0.1 mm (one unit equals one tenth of a millimeter) |
| Max stitch jump per step | ±121 units (±12.1 mm) per axis per stitch record |
| Machine commands | Normal stitch, jump, trim, color change, stop/end |
| Color information | Color-change count only (CO: field); actual thread colors are not stored in the file |
| Key header fields | LA: (design label), ST: (stitch count), CO: (color changes), +X:/-X:/+Y:/-Y: (design extents), AX:/AY: (end-point offset) |
| MIME type | application/octet-stream |
| Coordinate encoding | Relative X/Y offsets, bit-packed within each 3-byte stitch record |
| Embroidery scope | Stitch data only; no thread color palette, no font or text data, no layer information |
| Format origin | De facto universal commercial embroidery interchange format since the 1980s |
| Released | Tajima DST, 1980s - the de facto universal embroidery interchange format |
| Open standard | Yes · royalty-free |
DST conversions
Community Q&A
asked by usersNo questions yet - be the first to ask about DST files.
