They are the same geometry
The final contour is normalised exactly once, before either exporter runs, so both files start from an identical shape with its bottom-left corner at the origin.
SVG then flips Y, because SVG's Y axis points down. A vertex at internal (10, 4) in a part of height H becomes (10, H − 4) in the SVG and stays (10, 4) in the DXF. Importers that understand each format put the part back in the same physical place.
That single shared normalisation is deliberate: if each exporter normalised on its own, the two files could drift apart by a rounding digit and nobody would notice until a part came off the machine.
When to pick SVG
SVG carries physical dimensions for drawing apps such as Inkscape and for SVG-compatible CAM. LightBurn also imports vectors for laser workflows; it does not create end-mill pocket toolpaths.
It must carry width and height in millimetres plus a viewBox of 0 0 w h with the same numbers. Omit either and importers fall back to 96 units per inch, which is where the familiar 3.7795 scale error comes from.
Reliefs are written as A commands — true circular arcs — rather than cubic approximations. Bézier curves survive the round trip visually but tessellate badly in CAM, and the tessellation error lands exactly on the fit surface you care about.
When to pick DXF
DXF R12, identified as AC1009 in the header, is the right default for Carbide Create, Fusion's DXF import, and a great deal of older Windows CAM still running in shops.
The file contains LINE and ARC entities only. Arcs are stored as a centre, a radius, and start and end angles measured counter-clockwise, which is a lossless way to describe the relief.
There is no unit field worth trusting in R12, so the import dialog that asks you is not optional — pick millimetres. Beyond that, DXF is the more predictable of the two formats because there is no viewport concept to misread.
Things that go wrong
Do not convert SVG to DXF through an online converter. Those tools routinely explode arcs into polylines, apply a 96 dpi assumption, and occasionally mirror Y twice. The two buttons on this page share one contour and one normalisation; a converter adds a third opinion.
If a CAM tool only accepts polylines it will tessellate the DXF ARC on import. That is still better than a Bézier from a drawing app, because the tessellation starts from a true circle of radius R rather than from an approximation of one.
File size is negligible either way. Check your importer’s supported formats and measure the result: Carbide Create has a DXF workflow and Easel has an SVG workflow. LightBurn is a laser workflow, not an alternative CNC pocket CAM.
Preparing SVG input and resolving blocked downloads
Choose a local SVG file or paste its source. The generator accepts a single closed straight-line path or polygon using M, L, H, V and Z. Curves and multiple contours are rejected; simplify the drawing to one closed straight-line outline in your drawing app.
If the source has no known physical scale, enter its measured outline width in millimetres. Export stays disabled until calibration is valid. Replacing a file or its source clears the previous calibration, so each new drawing establishes its own scale.
An edge-length conflict also blocks both exports. Reduce the cutter diameter, switch relief style, or disable one corner using the numbered buttons. Confirm the new outer extent before you download. The output remains a finished pocket contour, not G-code.
Neither file is G-code
Both downloads are part geometry. Feed rates, plunge rates, ramps, tabs, and depth per pass all live in CAM, and this site will never write them.
That also means both files are the finished pocket contour rather than a cutter-centre toolpath. Import, set the same bit diameter, and let CAM do the offset once.