Free online SVG to NC converter

What the SVG format is

SVG (Scalable Vector Graphics) is an XML-based vector format that stores paths, shapes, text, fills, strokes, transformations, and dimensions. It is used for 2D profiles, engraving artwork, technical illustrations, laser-cut layouts, and simple CAD geometry.

Inkscape, Adobe Illustrator, CorelDRAW, browser-based drawing tools, and some CAD applications create SVG files. You may encounter SVG when exporting a drawing from a design program or downloading a vector profile for CNC fabrication.

What the NC format is

NC is a numerical-control program containing ordered machine commands, commonly G-code such as rapid moves, linear cuts, arcs, spindle control, feed rates, and coolant commands. Extensions include .nc, .cnc, and .tap, depending on the controller and CAM software.

NC is used by CNC mills, routers, lathes, plasma tables, and other programmable machines. Its main advantage is direct machine execution, but NC is not a single universal standard: a file for GRBL may require different commands from one for Haas, Mach3, LinuxCNC, Fanuc, or a laser controller.

How to actually convert SVG to NC

For a quick conversion, you can use the free converter on 101convert.com: upload the SVG, select NC as the output, start the conversion, and download the resulting file if the service supports the required SVG geometry and controller format. Treat the downloaded file as a starting point and verify it in a simulator or the machine manufacturer's software before cutting.

For reliable machining, use CAM software because it lets you define the toolpath and postprocessor:

1. Open the SVG in Inkscape or another vector editor.
2. Convert text and stroked artwork to paths. In Inkscape, use Path → Object to Path and, where necessary, Path → Stroke to Path.
3. Remove fills, duplicate paths, open contours, clipping masks, and construction objects that should not be machined. Confirm the drawing units and scale.
4. Import the cleaned SVG into a CAM program such as FreeCAD Path, Estlcam, VCarve, or Fusion. In FreeCAD, use the Draft workbench to import the SVG, then create a machining job in the Path workbench.
5. Set the stock size, work origin, material thickness, tool diameter, cutting depth, step-down, feed rate, plunge rate, spindle speed, safe height, and cutting direction.
6. Create the appropriate operation: profile for outside or inside contours, pocket for filled regions, engraving for centerline work, or drilling for recognized holes.
7. Select the postprocessor matching the controller, generate the toolpath, and export the NC program. In FreeCAD, use the Path workbench's postprocessing command and save the generated file as .nc when appropriate.
8. Simulate the toolpath, inspect the first and last moves, and run the machine above the workpiece or in air before cutting material.

Quality, compatibility, and limitations

SVG describes geometry, not manufacturing intent. It normally has no material, tool, cutting depth, feed, spindle speed, origin, workholding, kerf, or controller information, so a direct conversion cannot determine a safe toolpath without additional settings.

Check SVG units carefully: a file exported in pixels can acquire the wrong physical size when imported as millimeters or inches. Measure a known feature after import. Curves may be converted to many short line segments, and excessive nodes can produce large, slow, or uneven NC programs.

Fills do not automatically define pockets, overlapping paths can cause repeated cuts, and an open contour may not produce a closed profile. Text must be converted to paths, and unsupported SVG effects such as gradients, filters, masks, and embedded raster images generally have no machining equivalent.

Use the machine-specific postprocessor rather than renaming a file extension. Confirm units with the generated G20 or G21 command, inspect absolute or incremental positioning such as G90 or G91, and verify that spindle, laser, coolant, and tool-change commands suit the controller.