STL Viewer: 3D Model & 3MF

STL Viewer is an offline 3D model viewer for Android phones and tablets. Open STL, 3MF, OBJ, PLY, OFF, 3DS, GLB and glTF files, measure them, estimate the print, see them in AR at real size and convert them to STL. Your models never leave your phone and no account is needed. AT A GLANCE • 8 file formats: STL, 3MF, OBJ, PLY, OFF, 3DS, GLB, glTF • Works offline: no upload, no sign-up • No subscription and no in-app purchase • No pop-up, timed or full-screen ads; at most one small banner • 17 languages STL VIEWER FOR 3D PRINTING Check a part before you print it. Open the STL or 3MF you got from a model site or your slicer, look at it from every side and measure it. MEASURE AND ESTIMATE THE PRINT • Measure the distance between any two points, in millimetres • See dimensions, volume, surface area and triangle count • Print estimate: weight, filament length, print time and cost, by printer class, material (PLA, PETG, ABS, ASA, TPU, Nylon), layer height, infill and walls • Cut through the model with a section view VIEW IN AR (BETA) Place your model on a real desk or floor and see its true size before printing. AR runs on your phone; your model is never uploaded. It needs a phone that supports Google Play Services for AR. CONVERT TO STL Turn an OBJ, 3MF, PLY, OFF, 3DS, GLB or glTF model into a binary STL in millimetres, ready for any slicer. Every triangle of the source is kept. INSPECT EVERY DETAIL • Orbit, pan, zoom and fit to screen • Shaded or wireframe, perspective or orthographic • Front, back, left, right, top and bottom views from the view cube • Change the colour and the surface look: plastic, glossy, wood, stone or carbon • Files without an extension open too: the format is read from the file SHARE • A rotating 360° GIF • A 9:16 video for stories • An STL copy, only when you choose 3MF, OBJ AND GLB VIEWER 3MF is the format most modern slicers save; STL Viewer reads the geometry inside it with real-world units. OBJ, GLB and glTF open as geometry. Textures, materials and animations are not loaded, and native CAD formats (STEP, IGES) need to be exported to STL, OBJ or 3MF first. LOCAL AND PRIVATE Models are processed on your phone. STL Viewer does not send model files, filenames, geometry or dimensions to any cloud service, advertising provider or analytics platform. QUESTIONS AND ANSWERS How do I open an STL file on Android? Tap Open file in STL Viewer, or choose STL Viewer from "Open with" or Share in your file manager, browser or messaging app. Does STL Viewer work offline? Yes. Opening, measuring, the print estimate and STL export run on your phone without an internet connection. Can I open a 3MF from my slicer? Yes. The part's geometry opens with its real units; print settings and plates are not read. Can it estimate filament and print cost? Yes. Print estimate shows weight, filament length, time and cost from the part's volume and your settings. It is an estimate, not a slicer result. How do I convert OBJ, 3MF or GLB to STL on Android? Open the model, tap Export, then Share as STL. Can I see an STL in AR? Yes, on phones that support Google Play Services for AR. Tap the AR button in the tool panel. STL Viewer is for viewing, measuring, sharing and STL export. It does not edit, repair, slice or print models.