Convert PNG to DXF
Trace a PNG to a cuttable DXF outline in your browser, at a width you set in millimetres. You choose the brightness that separates the shape from the background.
Trace your image
Open the drawing workspace, choose your image, and set the threshold and the width. The file stays in your browser.
What this keeps and what it drops
Kept
- The boundary your brightness threshold draws, holes included
- The proportions of the image, scaled to the width you set
- A closed outline per shape, ready to cut
Dropped
- Colour, shading and anything between solid and empty
- Detail finer than the 256 pixel trace
- Smooth edges, because the outline follows pixel boundaries
You choose the threshold and the width, so there is no single result to measure. What is fixed is where the outline comes from and how coarse it can be.
What tracing does
A PNG is a grid of coloured pixels. A DXF is a set of lines a machine can follow. Getting from one to the other means deciding, for every pixel, whether it is part of the shape, and then drawing the boundary between the parts that are and the parts that are not.
You make that decision with one number. Everything darker than the brightness threshold counts as solid, and you can invert it when your artwork is light on a dark background. Move the threshold and the outline moves with it, so a logo that traces badly at the default usually traces cleanly a few steps either way.
Set the size while you are here
An image has no physical size, so the workspace asks for one. Give it the width in millimetres and the height follows from the image's proportions. That is the number your cutter cares about, and getting it right here saves scaling the DXF afterwards in software that may or may not respect the unit.
Once it is traced you have an ordinary drawing, so you can measure between two points, convert the units, or resize it to a target dimension before you export.
What comes out
One closed outline per shape, on a single layer, in millimetres. Holes stay holes. Straight runs are merged, so a horizontal edge is one line rather than one line per pixel, which keeps the file small enough for a cutter to load.
The outline follows the edges of pixels, so it is stepped rather than smooth. The trace runs at 256 pixels on the longest edge, and on a 100 mm wide job each step is about 0.4 mm. For a bold logo that is invisible in the cut. For fine lettering it is not, and vector art gives a better result.
When to use something else
If you already have the artwork as an SVG, use SVG to DXF. The outlines are exact at any size and nothing is thresholded.
If you want a solid to print rather than a path to cut, PNG to STL extrudes the same silhouette.
Limits
Images are limited to 25 MiB, 4 million pixels and 8,192 pixels on either side, and are traced at 256 pixels on the longest edge. Photographs rarely have one brightness that separates the subject from its background.