What Is a Laser Cut File and What Should It Contain?
A laser cut file is a vector drawing, usually SVG or DXF, that tells a laser where to cut and engrave. A good file has closed paths at real-world size (mm), a hairline CUT line, filled ENGRAVE areas on a separate layer, no duplicate lines, and notes about material thickness.
Download a file, click Start, and out comes a perfect reindeer. It feels like magic, but the magic lives in the file: a tidy set of lines that the laser can follow without guessing.
A laser cut file is a vector drawing, made of lines, curves and shapes rather than pixels, that tells a laser cutter where to cut, engrave or score. Because it is vector, it can be scaled without blurring and it describes a path the laser head can follow.
What a good laser cut file contains
| Element | What it should look like | Why it matters |
|---|---|---|
| Format | SVG or DXF (sometimes AI or PDF) | Opens in LightBurn, xTool, Glowforge and others |
| Size | Real-world dimensions, usually mm | Parts come out the right size |
| Cut paths | Closed shapes, thin hairline stroke, one color (for example red) | Laser treats them as cut lines |
| Engrave areas | Filled shapes in another color (for example black) | Laser fills them with raster lines |
| Layers | Separate CUT and ENGRAVE (and SCORE if needed) | You set different power and speed per layer |
| No duplicates | One line per edge | Avoids cutting the same line twice |
| Material note | Thickness, such as 3 mm plywood | Joints and holes are designed for it |
DXF World files follow this: SVG with a red CUT hairline and black ENGRAVE fill, DXF with layers CUT and ENGRAVE. Each product page lists the real size and cutting time.
What a laser cut file is not
- A photo. JPG and PNG are pixels. They can be engraved but not cut; you must trace them first, see How to Turn an Image into a Laser Cut File.
- A 3D model. STL or STEP files do not cut on a flat laser, though they can be sliced into flat parts.
- A G-code program. G-code is the machine's own instructions, often created from the file by software like LightBurn.
Warning signs of a bad file
| Problem | What you see | Fix |
|---|---|---|
| Open contours | Shapes do not fill or cut through completely | Fix open contours |
| Double lines | Machine cuts the same edge twice, doubling time and burning | Delete duplicates |
| Wrong size | Design appears tiny or huge | Why is my SVG the wrong size |
| Text not converted | Letters change font or vanish | Convert text to paths |
| Stroke is thick | Software treats it as an engraving, not a cut | See What Is a Hairline Stroke? |
Common mistake: Downloading a pretty image from a search engine and trying to cut it. A picture of an ornament is not a cut file: it has no closed paths, no layers and no scale.
Worked example
The DXF World reindeer ornament is 90 × 124 mm. It has one red outline with a 4 mm hanging hole (the CUT layer, 0.47 m of cut length) and black antler and fur details (the ENGRAVE layer). Open it in LightBurn: two layers appear, you set the cut to 100% power at your tested speed and the engrave to a lighter setting, and the first job takes about 1 min 48 s on a 10 W diode.
Pro tip: Before cutting any file, select everything and read the overall width and height. If it does not match the product page, fix the scale first.
Where to find legitimate files
Check the licence. CC0 files, like ours, can be used commercially without attribution; see CC0 vs CC BY vs Personal Use and our licence page. Browse the free library or compare formats in SVG vs DXF for Laser Cutting.
Next step
Open a file from the library, check size, layers and line count, and run a preview. Once you recognise a good file at a glance, you can design your own.
Questions and answers
What file formats do laser cutters use?
SVG and DXF are the most common. Many programs also accept AI, PDF and image formats such as PNG for engraving.
Can I cut a JPG on a laser?
You can engrave it as a raster image, but to cut its outline you must trace it into vector paths first.
What is the difference between a cut and an engrave layer?
Cut lines go through the material at slower speed or higher power; engrave areas are filled with many shallow lines at lower power.
Why does my file cut twice?
It probably has duplicate overlapping lines. Remove them before cutting.
Do laser cut files need to match material thickness?
Yes for joints and slots. A box file for 3 mm plywood will not fit together in 4 mm board.
Can I use files commercially?
Only if the licence allows it. CC0 files can be used for commercial products without attribution.