BSP to FBX Converter
FileFlip converts BSP to FBX entirely inside your browser, using Assimp compiled to WebAssembly. The file is never uploaded to a server: it is read off your disk, converted on your own machine, and saved back by the browser. That means no file-size limit, no queue and no account.
How do I convert a BSP file to FBX?#
- Drop your BSP file onto the converter at the top of this page, or click it to pick one from your computer. You can add as many as you like.
- Leave the target set to FBX and the conversion starts on its own. FileFlip downloads 11.2 MB of WebAssembly the first time and nothing after that, then runs Assimp on your own machine.
- Save the FBX file. Your browser writes it straight to your downloads folder, because there was never a server holding it.
Does converting BSP to FBX lose quality?#
Not in the sense of pixels or samples. Converting BSP to FBX rebuilds the file in FBX's own model rather than re-encoding it, so everything FBX can represent comes through exactly and anything it cannot has to be dropped. Expect the geometry to be exact, and anything the target has no place for, such as a rig, to be left behind.
Is it safe to convert BSP files online?#
Yes, because nothing is uploaded. FileFlip converts BSP files inside the browser tab you already have open, using WebAssembly builds of the same engines a desktop converter would install. Your file is read from your own disk into the page's memory, and no request carrying it is ever made.
You do not have to take that on trust. Open your browser's network panel, run a conversion, and you will see the engine come down and your file go nowhere. There is no upload, no server-side copy, no retention window, and no account tied to what you converted.
How FileFlip works lists every engine, its version and its download size, and shows how to check for yourself that nothing leaves your machine.
What BSP to FBX actually does to the file#
Converting BSP to FBX runs on Assimp, downloads 11.2 MB of WebAssembly the first time and nothing after that, rebuilds the file in the target's own model.
| Engine | Assimp |
|---|---|
| Conversion path | One step: BSP → FBX |
| Downloaded to your browser | 11.2 MB, once, then cached by your browser |
| Quality | Rebuilt in the target's model |
| You get back | One file |
| Where it runs | In a background worker, so the page stays responsive |
What survives the conversion
| What is in the file | This conversion | Why |
|---|---|---|
| Materials | Sometimes | Survives for some files and not others. |
| Textures | Sometimes | Survives for some files and not others. |
| Skeleton and animation | Sometimes | Survives for some files and not others. |
What is a BSP file?#
A BSP file is a compiled Quake III Arena level: an entire map's world geometry, pre-partitioned into a binary space tree, along with its lightmaps, texture references and entity placements, not a model of a single object.
Use BSP to ship or run a compiled Quake III Arena level; the original engine or a source port loads it together with its PK3 to render the map.
Convert a BSP file mainly to inspect or reuse its geometry outside the original game, since the format isn't meant to be edited directly; going back to the level editor's source .map file is the normal way to make changes.
What is an FBX file?#
An FBX file is Autodesk's proprietary binary or ASCII scene format, originally built by Kaydara for its Filmbox motion-capture software in 1996, that carries a full scene, meshes, materials, skeletons, skinning and animation together in one container.
Use FBX when a full rigged, animated scene needs to move between a DCC tool and a game engine, since almost every pipeline tool expects it.
Convert an FBX file when the destination needs an open, patent-unencumbered format, or when the application that wrote it isn't the one reading it and something is coming through wrong.
BSP to FBX questions people ask#
What is a BSP file?
A BSP file is a compiled Quake III Arena level, holding the map's entire world geometry pre-sorted into a binary space partition tree along with its lightmaps and entity placements. It's a level, not a single model, so opening one gets you the whole map's geometry rather than a prop.
Can I get a single object or prop out of a BSP file?
Not directly. A BSP stores one specific map's geometry already merged and partitioned for that layout, so there's no clean way to pull out an individual piece without rebuilding the partition and visibility data from source. The original .map file the level was compiled from is the format actually meant for editing.
What opens BSP files today?
The open-source ioquake3 engine and games built on it, like OpenArena, load BSP files exactly as Quake III Arena did, and level editors such as GtkRadiant and NetRadiant compile and inspect them directly.
What software opens FBX files?
Blender, Autodesk Maya, 3ds Max, Unity and Unreal Engine all open FBX files, since it's the format most 3D and game pipelines use to move scenes between tools. Which application wrote the file matters more than which one is opening it, because FBX exporters don't all interpret the format identically.