Why laser and CNC software wants DXF
Laser cutters and CNC routers move along paths. They need to know exactly where each outline starts and ends, and whether it is closed. DXF is the oldest and most widely supported format for that job, and almost every laser, plasma, vinyl and CNC program can import it. A DXF made from a traced image gives you clean contours to cut along, instead of a bitmap the machine can only engrave line by line.
How the DXF export works
The converter first traces your image into smooth outlines, exactly like the SVG preview you see above. On export, every curve is flattened into short straight segments (roughly 0.15 mm apart at your chosen size), and each outline is written as a closed polyline in DXF R12 format. R12 is the most compatible flavor of DXF, so even older software opens it. Holes, such as the inside of a letter O, are separate closed outlines, which is exactly what laser software expects for inner and outer cuts.
Step by step
- Add a high-contrast image. Black artwork on white works best. The Line art preset is selected on this page.
- Tune Threshold and Detail until the preview shows solid shapes with no stray dots. Every dot becomes a tiny cut, which wastes time and can burn the material.
- Set Output width in millimeters. The DXF uses millimeter units, so a 120 mm wide design imports at 120 mm.
- Export DXF (Pro). You can also download the SVG for free, which LightBurn and most laser software accept as well.
Design tips for laser cut parts
- Mind the bridges. For stencils and cut-out lettering, inner islands fall out once cut. Use a stencil font or add bridges in your editor.
- Avoid hairline details. Anything thinner than your material thickness tends to burn or snap. Raise Threshold to thicken thin strokes.
- Check kerf. The DXF follows the edge of your artwork. Apply kerf offset in your laser software, not in the drawing.
- Use layers. In color mode each color is saved on its own DXF layer, handy for mapping colors to cut, score and engrave settings.
Free SVG, Pro DXF
SVG download is free for single images. DXF export, batch conversion of many files into one ZIP, and larger inputs up to 16 megapixels are part of Pro. Everything still runs on your own computer, so your client artwork is never uploaded.
Frequently asked questions
Which DXF version do you export?
DXF R12 (AC1009) with closed POLYLINE entities, in millimeters. It is the most widely compatible DXF flavor.
Will the DXF open in LightBurn?
Yes. LightBurn imports DXF R12 polylines. Make sure the import units are set to millimeters.
Are curves kept as arcs or splines?
Curves are flattened into short straight segments about 0.15 mm apart at your output size, which is smooth enough for laser and CNC work and opens everywhere.
Can I convert a photo to DXF?
You can, but photos give many small shapes. For cutting, convert the photo to a silhouette with the Line art preset or the single-color cut file mode first.