SVG vs DXF for Laser Cutting: Which File Should You Use?

Pick up any free laser design and you will usually find two files in the folder: an SVG and a DXF. Both are vector formats, both will cut, and most laser software opens either. So which one should you use? The answer to SVG vs DXF for laser cutting depends on your machine, your software, and whether you care more about colours or exact geometry.

Here is a plain comparison, with the problems each format tends to cause and how to fix them.

The short answer

Use SVG if you run a Glowforge or xTool Creative Space, if your design has engraving fills, or if you rely on colours to separate cut, engrave and score.
Use DXF if the design came from CAD software (Fusion 360, FreeCAD, SolidWorks, AutoCAD), if dimensions must be exact, or if your machine software is an older controller program that prefers it.
In LightBurn, either works. SVG usually keeps colours more reliably; DXF usually keeps scale more reliably.

If you are not sure, try the SVG first and check the size after import. If the size is wrong and you cannot easily fix it, switch to the DXF.

What SVG is good at

SVG (Scalable Vector Graphics) is a web standard. It stores shapes, colours, fills and strokes, and can even hold embedded images.

Strengths for laser work:

Colours come through as exact RGB values. Red #FF0000 stays red #FF0000, so colour-coded layers land on the right operation.
Fills survive. A filled blue shape imports as a filled shape, ready for engraving.
Native to browser-based software. Glowforge's app and xTool Creative Space are built around SVG. Glowforge does not open DXF at all.
Easy to edit. Inkscape, Illustrator, Affinity Designer and CorelDRAW all open and save SVG.

Weak spots:

Scale problems. SVG can be written in pixels, and different programs assume different pixels per inch. Inkscape uses 96 per inch; some older programs assumed 72. The result is a design that imports at 75% or 133% of its intended size.
Hidden extras. SVGs from design programs can include clipping masks, groups, transforms and editor data that some laser software reads oddly.

What DXF is good at

DXF (Drawing Exchange Format) was created by Autodesk for swapping CAD drawings. It is plain geometry: lines, arcs, circles, polylines and splines.

Strengths for laser work:

Precise geometry. Arcs and circles are stored as true arcs, and dimensions are what the CAD file said they were.
Universal support. Almost every laser, CNC router, plasma and waterjet program reads DXF, including the software that ships with many Chinese CO2 lasers.
Clean for cutting. No fills, masks or effects to confuse the machine. A line is a line.

Weak spots:

Colours are limited. Most DXF files use a numbered colour index (1 is red, 3 is green, 5 is blue) rather than exact RGB. Common colours usually survive, but subtle shades can shift.
No real fills. Hatches exist, but laser software often ignores them. Engrave areas may arrive as outlines only, and you will need to set them to fill mode yourself.
Units can go missing. A DXF stores units in its header, but not every program writes or reads that value. A 100 mm part can arrive as 100 inches, or 3.94 mm.
Splines and versions. Some older software struggles with splines or newer DXF versions. Saving as R14 or 2000 is the safe choice.

SVG vs DXF for laser cutting: side by side

Here is how they compare on the things that matter at the machine.

Colour layers: SVG keeps exact colours. DXF keeps basic colours.
Engrave fills: SVG keeps them. DXF often loses them.
Scale: DXF is usually more reliable, SVG depends on how it was saved.
Curves: Both are good. DXF stores true arcs; SVG uses smooth Bezier curves.
Glowforge: SVG only.
xTool Creative Space: both, with SVG the smoother route.
LightBurn: both.
CAD round trip: DXF.
Text: both work best when text is converted to outlines before export.

Neither format stores laser power or speed. If you want settings saved with the design, use LightBurn's own .lbrn2 format. The wider picture, including EPS and PDF, is in laser cut file formats explained.

Common problems and fixes

The SVG imports at the wrong size. In Inkscape, set document units to mm and save as Plain SVG. In LightBurn, look at the SVG import options in the settings, which control how files without units are scaled. Or simply measure a known edge after import and scale to match.

The DXF imports tiny or huge. The units were lost. Scale by 25.4 (inches to mm) or 1/25.4, depending on which way it went. LightBurn and most CAD tools let you choose the unit when importing.

Colours merged into one layer. The DXF used one colour for everything, or a colour your software does not map. Select the lines by type and reassign them to layers by hand.

Engrave areas show up as outlines. Normal for DXF. In LightBurn, change that layer's mode from Line to Fill. Or use the SVG for engraving and the DXF for cutting.

Curves look jagged or cut slowly. The file stored curves as hundreds of tiny straight segments. Try the other format, or use your software's curve optimisation tool before cutting.

Lines cut twice. Both formats can contain overlapping duplicates. Run a "delete duplicates" or "remove overlapping lines" pass before every job.

Which one do professional files include?

The safest approach for anyone sharing or selling designs is to ship both. Different customers run different machines, and having the second format to fall back on solves most import problems. That is why downloads from the Digital Creation laser cut tool include SVG and DXF for every sheet, along with LightBurn, EPS and a 1:1 PDF, using red for cut, blue for engrave and green for score.

A quick test before you commit

When you are trying a new file, do this before cutting good material:

Import the SVG and the DXF side by side in your laser software.
Measure one known dimension on each. They should match the design size.
Check that each colour landed on its own layer.
Check that engrave areas are filled, not outlined.
Run a frame or outline trace on scrap to confirm the position on the bed.

Whichever passes first is the file to use. Mark the result in a note with the design so you do not repeat the test next time.

If the parts need to fit together, also allow for the width of the beam. The format will not fix a loose joint; a kerf test will tell you how much to adjust. And if you would rather start from a design that is already laid out in both formats, generate one from your own measurements and compare them yourself.

Frequently asked questions

Is SVG or DXF better for Glowforge?

SVG. The Glowforge app accepts SVG, PDF and image files, but not DXF. Convert a DXF to SVG in Inkscape first if that is all you have.

Is SVG or DXF better for LightBurn?

Both import well. SVG keeps colours and fills more reliably, while DXF tends to keep exact dimensions. Check the size after import either way.

Why does my DXF have no colours?

The program that saved it may have put every line on one colour or layer, or used colours your software does not recognise. Reassign the lines to layers manually.

Can I convert SVG to DXF?

Yes. Inkscape can open an SVG and save it as a DXF (choose the R14 option). Convert text to paths first, and check the size of the result.