Convert ASC to OBJ (Free)
Also converts STL, GLB, PLY, 3MF, FBX, glTF from the same file.
Runs in your browser. No upload, no signup, nothing to install.
Also from Innerscene: Circadian Lab, a free lighting calculator for room illuminance, melanopic EML, and glare.
How to convert ASC to OBJ
- 1
Open your .asc file
Drag it onto the viewer above, or click "Open an ASC File". Files up to 200 MB open directly; the parse runs in a worker so the page stays responsive.
- 2
Pick Wavefront OBJ in the Export menu
Click Export in the toolbar, then OBJ (.obj).
- 3
Download
The .obj is written in the browser and saved straight to your downloads folder. No queue, no email, no watermark.
What survives the conversion
A file conversion is a translation, and formats do not carry the same things. Here is exactly what moves from ASC into OBJ, and what does not.
| Geometry | Kept | Both formats store triangle meshes, so the shape transfers directly. |
|---|---|---|
| Colors and materials | Kept | OBJ carries material colors, which is at least what ASC stores, so the colors come across. |
| Units and scale | Dropped | OBJ stores no unit. Coordinates are written in meters, so set the import unit to meters if the destination asks. |
| Map coordinates | Kept | OBJ gets the map coordinates back: easting, northing and height on the ASC file’s own grid and in its own unit (a survey in US feet stays in US feet), Z up. Data stored in longitude and latitude is projected to its UTM zone, in meters. The zip includes a .prj when the source names its coordinate system. |
What the OBJ writer emits: OBJ plus a companion MTL, zipped together. Each layer becomes an object block and each mesh a named group with its material color. Lines are written as OBJ line elements and point clouds as point elements.
The source: Esri ASCII Grid (DEM) (.asc, .grd)
An Esri ASCII Grid (ArcInfo ASCII raster) as a terrain mesh in metres, coloured by height, with no-data cells left as holes; a ZIP of tiles, such as a LiDAR download, opens as one mosaic placed by each tile’s corner.
The target: Wavefront OBJ (.obj)
The lowest common denominator of 3-D interchange. Practically every 3-D application reads it.
Opens in: 3ds Max, Maya, Rhino, Cinema 4D, Blender, MeshLab.
Your file never leaves your computer
Both the ASC parser and the OBJ writer are JavaScript and WebAssembly running in your own browser tab. There is no upload step, no server-side conversion queue, and no copy of your file anywhere but your machine. That matters for drawings under NDA, for client work, and for anything you would not email to a stranger.
Free to Use, No Signup
There are no accounts and no watermarks on this converter. If it saved you time, the one thing we ask is a mention: a post, a link from your blog or course page, or a reply to someone asking how to open a file.
Share it
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Hear about new formats
Occasional emails when the viewer learns a new format or gets a new tool.
Frequently asked questions
▶Is this ASC to OBJ converter free?
Yes. No signup, no watermark, no per-file limit and no paid tier. Innerscene.
▶Is my ASC file uploaded anywhere?
No. The file is read with the browser file API and converted in the same tab. Nothing is sent to a server unless you explicitly click Share, which is a separate, opt-in feature.
▶Will my colors and materials survive the OBJ export?
OBJ carries material colors, which is at least what ASC stores, so the colors come across.
▶Will the OBJ open at the right size?
OBJ stores no unit. Coordinates are written in meters, so set the import unit to meters if the destination asks.
▶How large an ASC file can I convert?
Up to 200 MB, and the ceiling adapts to how much memory your device reports. The conversion runs on your own hardware, so a desktop with plenty of RAM will handle more than a phone.
▶Can I convert OBJ back to ASC?
Not here. We read ASC and write OBJ, but not the reverse. the universal 3D viewer
▶Which browsers does it work in?
Chrome, Edge, Firefox and Safari, on Windows, macOS, Linux, iOS and Android. No plugin and no extension.
Convert ASC to something else
Convert something else to OBJ
Or start from the universal 3D viewer.