Convert an Image to SVG for Laser Cutting (Free Methods)

A laser can engrave a JPG or PNG, but it cannot cut one. To cut a shape out, the laser needs a line to follow, and a pixel image has no lines. The answer is to convert an image to SVG for laser cutting by tracing it: turning the edges in the picture into vector paths. This guide shows how to do that in Inkscape and LightBurn, how to prepare the image, and how to clean up the result so it cuts well.

What tracing does, and what it cannot do

Tracing looks at an image, finds where light areas meet dark areas, and draws a path along each edge. The result is a vector file the laser can cut.

It works best on:

• Logos and simple graphics with solid colours.
• Silhouettes, such as a pet in profile or a building skyline.
• Line drawings and lettering with clean edges.

It works badly on full-colour photos with soft shading. A face in a photo is mostly gradual tones, and a trace turns that into blotchy shapes. For photos, you either engrave the image as it is, or simplify it first into a clear silhouette. If the photo is of an object you want to build, such as a phone for a stand, our laser cut file generator can work from the photo instead, and our guide on how to make a laser cut file from a photo covers that route.

Prepare the image first

Ten minutes of preparation saves an hour of cleanup. Before tracing:

1. Crop tightly to the subject.
2. Remove or whiten the background, so only the shape you want stays dark.
3. Turn up the contrast, aiming for strong black and white.
4. Use the largest image you have. Small images trace with jagged edges. Around 1000 pixels across the subject is a good minimum.
5. Fill small gaps in lines, so shapes close properly.

Any photo editor can do this, including free ones like GIMP.

How to convert an image to SVG for laser cutting in Inkscape

Inkscape is free and has one of the best built-in tracers. Here are the steps in Inkscape 1.x.

1. File > Import (Ctrl+I) your PNG or JPG. Choose Embed when asked.
2. Click the image to select it.
3. Open Path > Trace Bitmap (Shift+Alt+B).
4. On the Single scan tab, choose Brightness cutoff as the detection mode.
5. Set the threshold. Start around 0.45 and adjust until the preview shows the shape you want.
6. In the options, turn on Speckles to drop tiny dots, and keep Smooth corners and Optimize on.
7. Click Apply. The traced path appears on top of the image.
8. Drag the path aside and delete the original image.

Which detection mode to choose

• Brightness cutoff gives one solid shape. It is the best choice for silhouettes and logos.
• Edge detection traces the outline of edges. It often gives double lines, one either side of each edge, which a laser would cut twice. Avoid it for cutting.
• Color quantization splits by colour, which can help when two colours have similar brightness.
• Centerline tracing follows the middle of thin lines. Use it for line art that you want to score rather than cut.

The Multiple scans tab makes several stacked layers, which is useful for layered designs. Our guide to layered laser cut designs covers that approach.

Tracing in LightBurn

LightBurn has its own tracer, so you can skip Inkscape for simple jobs.

1. Import the image (Ctrl+I).
2. Select it and choose Tools > Trace Image (Alt+T).
3. Adjust the Cutoff and Threshold sliders until the preview outlines what you want.
4. Raise Ignore less than to drop small specks.
5. Adjust Smoothness so curves are smooth but corners stay sharp.
6. Click OK, then move or delete the original image.

The traced lines land on the current layer. Move them to your cut layer and check the size. For more on bringing files into LightBurn, see our LightBurn import SVG guide.

Clean up the trace so it cuts well

A raw trace is rarely ready to cut. Work through this checklist.

• Simplify the path. In Inkscape, Path > Simplify (Ctrl+L) removes extra nodes. Too many nodes make the laser stutter and leave a rough edge. Apply it gently, because too much rounds off corners.
• Delete tiny pieces. Anything smaller than about 1 mm across will either burn away or fall through the honeycomb bed.
• Check for islands. The centre of an "O" or "A" falls out when cut. If you want it to stay, add a small bridge to connect it, or engrave that part instead.
• Check thin parts. In 3 mm wood, parts much thinner than about 1.5 to 2 mm are fragile and may scorch. Thicken them or remove them.
• Set the style. Remove the fill, give the path a red stroke, and set the stroke to a hairline width (for example 0.025 mm) if your software cares about width.
• Set the size. Scale the traced shape to the final size you want, in millimetres, with the proportions locked.

Then save as plain SVG (File > Save As, choose Plain SVG in Inkscape) for the widest compatibility. If you will use a DXF-only program, export a DXF as well.

Combine cut, engrave and score

A good laser design rarely uses only cut lines. After tracing, think about which parts should do what:

• The outline is a cut line (red).
• Inner detail, such as eyes or fur texture, can be a filled engrave area (blue) instead of being cut out.
• Fine lines can be scored (green), which leaves a clean mark without weakening the piece.

This gives a stronger, more detailed piece than cutting everything. If you would rather skip the manual tracing entirely, our laser cut tool can draw a custom design from a photo and give you SVG, DXF, LightBurn, EPS and PDF files with colours already set.

Common tracing mistakes and fixes

• Jagged edges. The source image was too small. Use a larger image, or increase smoothing.
• Shape full of holes. The threshold is too low or the image has noise. Raise the threshold or clean the image.
• Double lines on every edge. You used edge detection. Switch to brightness cutoff.
• Thousands of nodes. Simplify the path, then check corners.
• Wrong size on the laser. The document units were not set. Set the document to millimetres before tracing and check the size after import.

As with every job, test on scrap first, and stay with the laser while it runs. Treat any settings as starting points, because machines differ.

Frequently asked questions

Can I laser cut a JPG or PNG directly?

No. You can engrave a JPG or PNG, but cutting needs vector lines. Trace the image to SVG first.

What is the best free software to convert an image to SVG?

Inkscape is free and its Trace Bitmap tool works well for logos and silhouettes. LightBurn's Trace Image tool is handy if you already own LightBurn.

Why does my traced SVG cut twice?

The trace has two lines on each edge, usually from edge detection. Use brightness cutoff instead, or delete one of the doubled lines.

Can I trace a photo of a person or pet?

Yes, but simplify it first. Remove the background and raise the contrast until you have a clear silhouette. Detailed photos are better engraved than cut.