Convert STL to SVG
An STL is a solid. An SVG is a flat drawing. There is no way to do this without losing a dimension, so the honest question is which flat drawing you want — and this tool asks you rather than guessing.
Drag a 3D file here, or.
This page is set up for STL files. Other formats we can read work here too.
The file is read on your own computer. It is never uploaded.
Your file is read by your own browser and never sent to a server. There is no upload, no account and no copy of your model anywhere but on your computer.
Two drawings, two different jobs
The outline is the shape of the model’s own shadow, looking straight down one axis. Use it to cut a backing plate, to trace round a part, or to see the footprint a model will take up on a bed. It is worked out from the model itself: every edge where the surface turns away from you is part of the drawing, which is why an L-shaped part comes out as an L, inside corner and all.
The cross-section is the shape of a cut straight through the model at a chosen height. Use it for a profile, a gasket, a template, or to check the wall thickness somewhere inside a part. On a watertight model every loop closes properly, which is what makes the result usable as a cutting path rather than just a picture.
Both are offered because neither is the right answer for everybody. Pick one from the box above the button, and pick the axis you are looking down — Z for straight from above, X or Y from the sides.
The size is real
The drawing is written at the true size of the model, with the unit stated in the file header. Set the output unit to millimetres and a 30 mm part produces a 30 mm drawing; set it to inches and you get the same drawing measured in inches.
That matters more here than anywhere else on this site. A laser cutter reads the width and height out of the header, and a drawing that opens at the wrong size cuts a part at the wrong size out of real material.
What the file looks like
Plain paths, no fill, a hairline black stroke. That is what a laser cutter, a vinyl cutter and a CNC router all expect: a fill is ambiguous about whether the machine should follow the edge or clear out the middle, and a stroke is not.
It opens in Inkscape, Illustrator, LightBurn, Lightburn’s importers, Fusion 360 and any browser. If you want it filled instead, that is one change in any of those programs after opening it.
What you cannot get back
Everything in the third dimension. A drawing has no thickness, no surface, no far side. Two features at different heights that happen to line up become one line. A cross-section through the middle of a hollow part shows the wall, not the outside.
This is not a limit of this tool — it is what flattening means. If you want the model back afterwards, convert the SVG to STL and give it a thickness, but understand that what comes back is an extrusion of the drawing rather than the part you started with.
What survives, and what does not
Kept in the SVG file
- The true size, with the unit written into the file header
- Closed loops, so the drawing can be used as a cutting path
- Inside corners and internal edges, because they are real features
- Every separate loop, including the holes in the middle of a part
Lost on the way
- The third dimension, which is the whole point of flattening
- Colour, material and texture
- Anything hidden behind something else along the axis you chose
- Curved surfaces, which become straight-line paths
How to convert STL to SVG
Drop the .stl file in
The model appears in the 3D view. Both forms of STL are read and the mesh is welded first, which is what lets the cross-section produce closed loops.
Choose outline or cross-section
Outline gives you the shape of the model’s shadow down one axis. Cross-section gives you a cut straight through it at a chosen height. They answer different questions.
Pick the axis you are looking down
Z is straight from above, which is what you want for a footprint or a backing plate. X and Y look from the sides.
Set the height, for a cross-section
The slider runs from the very bottom of the model to the very top. An empty result means the plane missed the model entirely.
Set the output unit and download
Millimetres for a laser cutter. The unit is written into the SVG header, which is what the cutter reads to open the drawing at the right size.
STL and SVG compared
| Property | STL.stl | SVG.svg |
|---|---|---|
| File contents | Binary or plain text. Binary is an 80-byte header, a triangle count, then 50 bytes per triangle. | XML. A text description of shapes, readable and editable by hand. |
| Geometry | Triangles only. Curves are approximated when the file is made, and cannot be recovered. | Flat paths: lines, arcs, and cubic and quadratic Bézier curves. |
| Units | None. The file stores bare numbers, and every reader has to guess what they mean. | Real units are allowed — mm, cm, in — but most files use bare user units. |
| Colour and texture | None. There is no place in the format for a colour, a material or a texture. | Fills, strokes, gradients and patterns, none of which describe a solid. |
| Separate objects | One body. Several parts written into one STL become one undivided lump of triangles. | Groups and layers, with ids and names on both. |
| Published by | 3D Systems, 1987, for the first stereolithography machines. | The W3C, 1999. Version 1.1 is what tools write; SVG 2 is still arriving. |
| Written by | Every CAD program and every slicer, as the common denominator. | Illustrator, Inkscape, Affinity Designer, Figma and every drawing program. |
Questions
- Which should I pick, outline or cross-section?
- Outline if you want the shape of the part as seen from one side — a backing plate, a template to trace. Cross-section if you want to see inside it, or need the profile at a particular height.
- Why does my outline have lines inside it?
- Those are real edges where the surface turns away from you — the rim of a recess, the top of a step. They are part of what the model looks like from that direction. Delete them in your drawing program if you only want the outer boundary.
- Can I cut this straight away?
- Usually yes, once you have checked the size. The file states its own width and height in millimetres or inches, so a cutter that reads them opens it at the right scale. Check in your cutting software before you start the machine.
- The cross-section came out empty.
- The plane missed the model. Move the height slider — 0% is the very bottom, 100% the very top — or try a different axis.
- Can I get a DXF instead?
- Not yet. DXF is the other format laser cutters read, and it is coming. Most cutting software imports SVG today, and Inkscape will save an SVG as a DXF in the meantime.
- Why are the curves made of straight lines?
- Because the STL already was. The curved surface was flattened into triangles when the STL was written, and a cross-section through triangles is straight segments. The information to draw a true arc is not in the file.
Having it cut
If you do not have a machine, these will cut this drawing from sheet material and post it to you. Upload the file you just downloaded; all three quote from it directly.
- SendCutSendLaser-cut sheet metal and plastic, no minimum order
- PonokoLaser cutting in acrylic, wood and card, single pieces
- PCBWayCNC machining and sheet metal from a drawing
These are ordinary links, not paid referrals — we earn nothing if you use them. The converter above is the same whether you do or not.
Where to go next
The other direction
Other things to do with a STL file
Other ways to get a SVG file
Related guides and tools
- Gridfinity generatorBins and baseplates, any size, built in the browser
- Turn text into an STLType a word and print it, without drawing anything
- Turn an image into an STLA photo or a logo, turned into something you can print
- Lithophane generatorA photo printed as thickness, lit from behind
- Repair an STL that will not sliceClose the holes and separate the bad edges so a slicer accepts it
- STL to G-codeGuide
- How to convert an STL file to G-codeGuide
- Convert STL to DWGGuide
- How to turn a PDF into an STLGuide