Convert AC3D to DAE
Free, in your browser, with nothing uploaded. Drop your .ac file in and take the .dae away.
Drop your AC3D file here
.ac in, .dae out
Choose filesNothing is uploaded No account, no email No file size limit
How to convert AC3D to DAE
- 01
Add your .ac file
Drag your AC3D Model file onto the drop zone, or click it to browse. Nothing is uploaded: it is read where it already sits.
- 02
Check the preview
The model is parsed on your machine and drawn in the viewport, so a wrong axis or a missing texture shows up before you commit rather than downstream.
- 03
Save the .dae file
Press convert. The COLLADA file is written in the tab and lands in your downloads folder. No link, no expiry, no account.
What carries over, and what does not
A format conversion is a translation, and translations lose things. Here is what actually happens when an AC3D file becomes a DAE file.
| Data | AC3D | DAE | Survives |
|---|---|---|---|
| Geometry | Yes | Yes | Yes |
| Materials & colour | Yes | Yes | Yes |
| Texture maps | Yes | Yes | Yes |
| Animation & rigs | No | Yes | n/a |
| Scene hierarchy | Yes | Yes | Yes |
This is a comparatively lossless pairing: 4 of the five categories above are supported by both formats, so most of what is in your AC3D file has somewhere to go in the DAE file.
What our DAE writer puts in the file
COLLADA 1.4.1, with geometry, Phong materials and textures embedded as data URIs. Animation is not written, and the scene is flattened to one node per mesh with transforms baked in.
About AC3D Model
AC3D files are a compact text format listing objects, their vertices, surfaces and materials in a nested hierarchy. AC3D itself was an inexpensive, focused modeller that the flight-simulation community adopted wholesale, and the format became the standard for FlightGear aircraft and scenery, which is why so much simulator content still arrives as .ac.
Commonly seen in: AC3D, FlightGear, X-Plane tooling, flight-sim scenery. More on the AC3D format page.
About COLLADA
COLLADA is an XML-based interchange format standardised by Khronos in 2004 as a vendor-neutral answer to FBX. It carries geometry, materials, shaders, physics, animation and full scene hierarchy, all in readable XML, and files get enormous as a result. Khronos has since moved on to glTF, but COLLADA is still what SketchUp, older Google Earth content and a long tail of CAD exporters emit.
Commonly seen in: SketchUp, Blender, Godot, Google Earth, Maya. More on the DAE format page.
How the conversion works
When you drop a file in, the bytes are handed to a parser compiled to run in your browser. The AC3D data is decoded into an in-memory scene graph of meshes, materials and transforms, which is what the preview is drawing. Pressing convert walks that scene graph back out through a DAE writer and hands you the resulting bytes as a download.
The whole round trip is local. The page itself is static: it is delivered once and then does its work offline. That is why the privacy claim is checkable rather than a promise.
AC3D to DAE: common questions
Is my AC3D file uploaded anywhere?
No. The file is read by code running inside this browser tab and never crosses the network. You can prove it by disconnecting from the internet before you convert, the page keeps working, or by watching the Network tab in your browser's developer tools while you drop a file in.
How large an AC3D file can I convert?
There is no server-side limit because there is no server. The practical ceiling is your own machine's memory: a browser tab can usually handle models up to a few hundred megabytes. Very dense scans or scenes with millions of triangles will take a few seconds and a lot of RAM.
Why does my converted DAE file look untextured?
DAE does support textures, but the images have to be available to embed. If your AC3D file references texture images that live next to it on disk, drag those images into the drop zone along with the model and they will be picked up.
Does it cost anything?
No. There is no fee, no account, no watermark and no per-file limit. Since the conversion runs on your hardware rather than ours, serving this page costs about as much as serving a blog post.
Does it work on a Mac, on Windows or on a phone?
All of them. There is nothing to install: any browser with WebGL 2 will do, which covers current Chrome, Edge, Firefox and Safari on desktop, and Safari and Chrome on mobile. A phone has less memory than a laptop, so a very heavy scene may be the one thing it cannot finish.
Related conversions
Other things to do with the same file.
From AC3D:
Other ways to get to DAE:
Or do something else with it: