View and inspect
3D models on Windows

Installation

3D Explorer is distributed through the Microsoft Store as a single package that installs both the desktop app and the Windows Explorer shell extensions.

🔄 What gets installed

The Interface

3D Explorer has a simple left-hand navigation. You can open a model by clicking Open a model…, dragging a file onto the window, or launching it from Windows Explorer.

📂 Opening a model

1. From Windows Explorer. Double-click a 3D file, or right-click it and choose Open with 3D Explorer. From the preview pane, the right-click menu has Open with 3D Explorer.
2. From the app. Click Open a model… on the Home page, or Open another 3D file… on the Model page.
3. Drag and drop. Drop a file anywhere on the window.
4. From Recent. Pick a model you opened before.

Windows Explorer Integration

Once 3D Explorer is installed, Windows Explorer gains thumbnails, a live preview pane, and file details for 3D files — no extra steps required.

⚡ How thumbnails and previews stay fast

Explorer asks for a thumbnail for a whole folder at once, and a single scan or sculpt can hold a hundred million triangles, so the handlers work to a budget. A model above the ceiling is simplified for its picture, a read that runs past the time limit shows what it got and says so, and both ceilings are yours to raise in Settings. The app itself has no such budget, a model you opened deliberately is drawn in full.

Two kinds of file skip the work entirely. A 3MF package and a sliced G-code program often carry a picture their authoring tool already rendered, and that picture is decoded and returned as the thumbnail, with no geometry read at all.

👁️ Using the preview pane

The 3D Explorer preview pane is a compact version of the full viewer, and it is live rather than a picture. Drag to orbit, hold the middle button to pan, scroll to zoom, and right-click for the rest:

Better Shell Integration (all users, administrator required)

3D Explorer can register its handlers with Windows itself, for every user on the PC. This turns on the model thumbnails, the preview pane, and the Explorer file details / properties for all supported 3D files. Because it changes the machine, Windows asks for administrator approval when you turn it on or off.

🛠️ Install, update, uninstall

Everything is done from Settings → Shell Integration. The card shows the current status and the matching action button, and each action prompts for administrator approval (a standard Windows UAC dialog).

⚙️ Why it needs administrator, and why updates are separate

Windows resolves thumbnail and preview handlers from a machine-wide location that only an administrator can write. So this integration installs for all users and asks for approval. It's copied to a stable per-machine folder, so it keeps working across app updates and even if the Store app is removed. Because it lives outside the app package it doesn't update itself, so a newer app version flags update available and one click refreshes it.

Viewing Models

The Model page is the viewer. A toolbar runs above the model and wraps rather than hiding anything in a menu, and it always follows the view — drag the model and the zoom box updates itself.

🖱️ Orbit, pan & zoom

The angles and the zoom are shown in the bottom-left corner of the view, so you always know where you are. A model turns around what you are looking at rather than around its original centre, so panning to a detail and then orbiting keeps that detail in front of you.

🔍 Fitting and resetting

🎨 Background colour

The Background color button opens a colour picker for the view. Transparent hands the choice back to the app, which then uses a backdrop that matches your Windows theme. The same colour is used by the Explorer preview pane, and it is remembered between sessions.

Views, Grid & Wireframe

Three toggles change how the model is drawn and how many ways you look at it. They apply at once and they combine.

🕸️ Wireframe

Draws the triangle edges instead of the shaded surfaces. It is how you see the density of a mesh, where a scan is heavy and where it is coarse, and the seams a shaded view hides. The wireframe's colour follows the background by default, and you can force one in Settings.

🧭 Ground grid and axes

Puts a grid on the plane the model stands on, with the three axes at its centre — X red, Y green and Z blue, the convention every modelling tool uses. The squares are a round number of the model's own units, so the grid also tells you how big the thing is. The grid's colour is worked out from the background, so it reads on a dark backdrop and on a light one.

🪟 Four views

Splits the view into the 3D view at the top left plus straight Front, Side and Back views, each labelled in its corner. The three straight views are orthographic, so a length reads true and parallel edges stay parallel, which is what makes them useful for checking proportions.

Model Properties

The Properties button on the Model page opens everything the product knows about the open file. It is the same set the Explorer details pane publishes, so the two can never disagree.

🪟 In Windows Explorer

The same facts reach the Explorer Details pane, mapped onto the Windows properties every application understands, so they also show in the tooltip and in any column you add to a folder view.

Exporting

The Export page writes what is open as a picture, a drawing, another 3D model, or a CAD file. Pick a format, choose the views and the sizes, and everything else on the page follows the choice.

🧭 Views and sizes

Tick any of 3D, Front, Side and Back, and give one or more sizes in pixels separated by commas. Each combination becomes a file. A PDF or an SVG takes its page size from the same number. A model file and a 3D drawing carry the whole scene, so they ignore the view.

🏷️ File names

The File name box is a pattern rather than a name, and the page shows an example of what will be written as you type. The tokens are listed in File Name Tokens.

✏️ Drawing style, outline and wireframe

A PDF, an SVG or a flattened CAD drawing can be drawn three ways: Shaded surfaces, Outline only, or Outline over the surfaces. An outline is the silhouette plus the edges sharp enough to read as edges, with whatever sits behind a surface left out, which is a fraction of the size of a shaded drawing and much closer to a technical drawing. Edge angle decides how sharp an edge has to be to show, Line width and Line color do what they say, and Automatic picks an ink that reads on the page. The wireframe option draws every edge instead of the surfaces, in a picture and in a drawing alike.

📐 DXF and DWG options

🏃 Running an export

Click Export, or press Ctrl+E. The page is busy while it writes, since a large model takes a moment, and a message tells you so rather than leaving the window looking frozen. When it finishes a toast says how many files were written and where, names anything written beside them, and says how many were left alone when a file of that name was already there and overwriting is off. Open folder takes you to the result. Anything that goes wrong is reported in the same place, with the reason.

The page also refuses an export that cannot work, before it starts: no folder, no name, no view, no size, or a name that would make several files overwrite each other. The message says which, and the Export button stays disabled until it is fixed.

📦 Files written beside the file

Some formats need company. An OBJ writes its .mtl material library and copies its textures beside it, a .gltf writes its buffer and its images, a PLY notes its texture by convention. A GLB or a 3MF packs everything inside the one file. The toast that appears when the export finishes lists what was written, side files included, and Open folder takes you straight there.

Recent Files

The Recent page keeps a list of the models you have opened before, so you can jump back to one quickly.

Settings

The Settings page groups the app's options. Viewing choices you make in context — zoom, background, the toggles, the export options — are remembered on their own.

Appearance and behaviour

Rendering

Reading limits

Every one of these can leave a preview partial, and a preview that was cut short says so. Raise one when you meet it.

Explorer integration

The About section shows the app version and a link to detailed System Information — useful when reporting an issue. Your export folder, name pattern, sizes, colours and background are remembered automatically between sessions.

Supported Formats

Input — what 3D Explorer reads

Meshes, whole scenes, and the toolpath programs a slicer or a machine tool produces.

Containers — a whole model in one file

A model is often a SET of files, an .obj with its material library and its textures. 3D Explorer opens them together from a folder, or from an archive:

Export

Raster exports cover the image formats registered on your Windows system. A green dot marks formats that keep transparency, a blue dot marks vector formats.

File Name Tokens

The File name box on the export page is a pattern. Tokens are case-insensitive, and a token the chosen format has no use for is simply left out of the name, so one pattern can serve every format.

Keyboard & Mouse

The same three gestures in the app and in the Windows Explorer preview pane.

Keyboard, in the app

Each one is also written in the button's own tooltip, so the toolbar teaches them as you use it.

In the model viewer

In the Windows Explorer preview pane

Limitations

3D Explorer is a fast, faithful viewer, inspector and converter — not a modelling tool, a mesh repair tool or a slicer. Knowing what it focuses on, and where a format itself sets the limit, helps set expectations.

🛠️ Viewing and converting only

There is no editing. You cannot move a part, retopologise a mesh, fix a non-manifold edge, hollow a model for printing or generate supports. Exporting to another format converts what was read, it does not repair or optimise it. Before you print or machine a part, check it in the tool that will make it.

🚫 Blender documents are not read

A .blend file is a memory dump of Blender's own internal structures rather than an interchange format, and reading its geometry means reimplementing Blender's type system and following it across releases. 3D Explorer does not read one. Export from Blender to glTF, FBX or OBJ and all three open here.

🧍 Animation, rigs and cameras

A rigged or animated scene is drawn in its bind pose, which is what a thumbnail of a character should be. Skins, animation stacks and poses are counted in the properties and nothing more. Cameras and lights in a scene are not used, the viewer lights every model the same way so two models can be compared.

🗜️ Compressed geometry

A glTF whose meshes are packed with the Draco extension is reported as unsupported rather than shown empty. Re-export it without Draco and it opens normally.

📏 Derived figures are estimates

The size in millimetres is the model's bounding box, and it depends on the unit the file declares. A format that declares no unit is taken at face value, so a model authored in centimetres and saved without saying so will read ten times small. The declared unit and up axis are always shown in the properties, so you can tell.

🧵 A toolpath is interpreted, not simulated

A G-code program is drawn by following its moves and giving them width, which shows the printed object or the path a tool takes. It is not a machine simulation, there is no material removal, no collision checking and no time estimate of our own beyond what the file states.

⚖️ Very large models are capped

Reading limits stop one file exhausting your machine, and the Explorer handlers apply a further budget so a folder of huge models never hangs File Explorer. When a limit is met the model still appears, marked partial, and the details say which one. Every limit is a setting you can raise, see Settings.

🥇 One thumbnail / preview provider per file type

Windows lets one handler own a file type at a time. If another application is registered for .stl or .obj, its thumbnails win. Better Shell Integration is the fix, it registers 3D Explorer machine-wide as a fall-through.

🚫 Preview stays blank for files downloaded from the internet

Starting with Windows 11 25H2, Microsoft blocks the File Explorer preview pane for files that carry the "Mark of the Web" — files downloaded from the internet, or coming from a location Windows considers unsecured. This affects every file type, not just 3D models, and it is a Windows security decision: there is nothing 3D Explorer can do at its level to override it.

Tips & Tricks

📦 Package a model as one shareable file

Zip the folder holding a model and everything it links to, then rename the archive to .3dzip — or, if you compress with RAR, to .3drar. Either one carries a 3D Explorer thumbnail and preview in Windows Explorer and opens as the complete model, textures included, with a double-click.

🖼️ A model that opens grey or untextured

Its textures are missing. 3D Explorer looks for them where the model says, then anywhere under the model's own folder, so the usual cause is that the images were never sent with the file. The bar over the view names the ones it could not find. Ask for the model as a GLB or a 3MF, both of which carry their images inside the file.

🔬 Reading a dense mesh

Turn on the wireframe to see how a model is built and where its detail is, and the ground grid to judge scale. Four views beside them is the quickest way to check proportions, since each straight view can be zoomed and panned on its own.

🥇 Thumbnails or previews don't show (another app is the default)

Windows follows the file type's default app for thumbnails and previews. If another program handles a 3D extension and is set as default, its thumbnails win. The quickest fix is Better shell integration:

1. Open 3D Explorer's Settings → Shell Integration (see Better Shell Integration) and click Install. Approve the administrator prompt.
2. 3D Explorer's thumbnails, preview and details now show for all supported files, for every user — regardless of which app is the default.

Prefer not to use the machine-wide option? You can instead make 3D Explorer the default app for an extension in Windows Settings → Apps → Default apps. Either way, run Settings → Reset Thumbnails if old cached thumbnails linger.

🔄 Thumbnails look out of date?

After changing colours or thumbnail settings, click Reset Thumbnails in Settings. You can also clear Windows' cache with Disk Cleanup: press Win+R, run cleanmgr, tick Thumbnails, and click OK.

🌙 Dark mode

3D Explorer follows your Windows theme by default. For a fixed look, choose Light or Dark explicitly in Settings. The view's backdrop, the wireframe ink and the ground grid all follow whichever you land on, unless you pick a colour of your own.