Free Online STL File Viewer
Manufacturings can open STL files and measure — bbox, distance, and section tools.
What is a STL file?
STL is a standard CAD exchange format used by manufacturing teams to review parts and assemblies. CADDaddy opens .stl files locally in your browser using WebAssembly — your file stays on your device until you choose to save or share.
What you can do with STL files in CADDaddy
CADDaddy helps manufacturing teams open STL files and measure. Drop a file, inspect geometry, measure dimensions, and export to STL or GLB — free to start.
Instant browser viewing
Open files in seconds. No install, no account required to start inspecting.
Trusted units & bbox
STEP/IGES load in millimetres with a unit chip and one-click L×W×H envelope.
Measure & section
Point-to-point distance, bounding box, and cross-section slices for review.
Export to STL or GLB
One-click mesh export for 3D printing, web, or downstream tools.
Works on phone & desktop
Review supplier files from a phone browser or factory PC — no CAD license.
Lifetime Pro unlock
$19 one-time for unlimited files, measure, section, and clean exports.
STL Viewer FAQ
How do I open a STL file online?+
CADDaddy helps manufacturing teams open STL files and measure. Drop a file, inspect geometry, measure dimensions, and export to STL or GLB — free to start.
Do I need SolidWorks or AutoCAD to view STL?+
No. CADDaddy opens .stl files in Chrome, Safari, or Edge with no desktop CAD license.
Can manufacturing teams measure STL files online?+
Yes. Free users get a measure trial; Pro unlocks distance, bounding box, face area, and section views for supplier review.
Is CADDaddy free?+
Viewing is free with no account. Guest export is limited daily; Professional is a one-time $19 lifetime unlock for unlimited files and tools.
Other formats CADDaddy supports
View your STL file now
No install, no account required. Drop your file and start inspecting.
Open viewer