Open the source surface
Choose an ASCII or binary STL and read its bounds in the workspace. Source coordinates are interpreted as millimeters because STL stores no units.
A REAL SECTION. REAL VECTOR PATHS.
Vector sections stay in your browser; files are never uploaded to create paths.STL to SVG Converter — Planar Cross-Sections
Convert STL to SVG by intersecting a triangle mesh with a plane at your chosen height. Select a top, front or side section, inspect the generated vector paths and download a millimeter-sized drawing. This tool creates a cross-section through the surface, rather than a camera screenshot or a projected silhouette of the complete object.
Loading your local 3D workspace…
Extract a Profile for Layout and Fabrication Planning
Use an STL to SVG converter to inspect an enclosure section, trace a packaging insert or compare a printed part's slice with a two-dimensional layout. A cylinder cut perpendicular to its axis produces a polygonal approximation of its circular perimeter.
When considering STL to SVG for laser cutting, treat the drawing as a starting profile. Check closed paths, overlapping shells, material thickness and kerf in your cutting software. An internal opening may produce a second contour, but the tool does not decide which regions to remove or generate a machine-ready toolpath.
How to Convert STL to SVG Cross-Sections
Choose a plane and its coordinate
Top uses XY with a Z height; Front uses XZ with a Y height; Side uses YZ with an X height. The default is the middle of the selected axis. Enter a section height strictly inside the displayed minimum and maximum, then select Create section.
Review contours and save the drawing
The STL to SVG result shows its width and height in millimeters, path count and number of open paths. Examine the vector preview before selecting Download SVG.
Triangle Intersections, Contours and Physical Units
STL to SVG evaluates each triangle against the selected plane and interpolates actual edge intersections. Matching endpoints are joined into contours using a small numeric tolerance. Degree-two connections become continuous paths; branches or broken surfaces may remain open paths. Duplicate segments are removed, but intersecting shells are not boolean-unioned.
The SVG uses vector path commands, not embedded bitmap pixels. Its width and height carry mm units, and its viewBox uses the corresponding numeric extents. Coordinates are shifted to a local drawing origin and the vertical axis is flipped for conventional SVG display. This changes drawing placement, not measured dimensions.
STL to SVG precision is limited by the tessellated source and its floating-point coordinates. A coarse circle remains polygonal; the conversion does not fit analytical arcs or reconstruct CAD constraints.
What This Converter Can't Do
STL to SVG does not generate a full orthographic projection, hidden-line drawing, unfolded surface or multiple layered slices. It cannot extrude SVG back into a solid. Sections at an outside height, at an axis boundary or coincident with a triangle face are rejected so ambiguous geometry is not presented as a clean profile.
The STL to SVG workspace accepts one input up to 25 MiB and 400,000 triangles. Complex surfaces can generate many segments and paths. Open meshes can produce gaps; touching or overlapping shells can need manual cleanup. JavaScript and Web Workers are needed for computation, with WebGL for the source preview. Export before leaving because models and sections are temporary.
A FEW THINGS TO KNOW
Questions About Vector Sections and Cutting Profiles
Does STL to SVG save a screenshot?
No. The download contains path commands calculated from triangle-plane intersections. You can inspect and edit those vectors in compatible software. The source preview is separate and its camera angle does not determine the section geometry.
Which height should I choose?
Start at the midpoint of the selected axis, then move to the feature you want to inspect. The coordinate is absolute within the original model bounds.
Why are there open paths?
An open or non-manifold source can yield disconnected sections or branches. The workspace reports open paths rather than silently closing gaps. Inspect the drawing and repair or redraw the profile where your downstream process requires closed loops.
Can I send the download straight to a laser?
Review it first in the machine's preparation software. Check scale, duplicate or intersecting contours, kerf, material and cutting order. This converter does not configure power, speed, safety interlocks or any device-specific instructions.
Will a circle become a smooth SVG arc?
No. The section follows the original triangle edges, so curved surfaces produce polygonal contours. A higher-resolution source can improve the approximation, but the output does not reconstruct analytical curves or promise CAD-exact dimensions.
Why is a plane through a flat face rejected?
Coplanar triangles create ambiguity about which edges belong to a section. The tool asks you to move the plane slightly instead of exporting overlapping face edges as if they were a reliable outline.