Convert ASC to DXF (Free)
Also converts STL, OBJ, GLB, PLY, 3MF, FBX 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 DXF
- 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 AutoCAD DXF R12 in the Export menu
Click Export in the toolbar, then DXF (.dxf).
- 3
Download
The .dxf 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 DXF, and what does not.
| Geometry | Kept | Both formats store triangle meshes, so the shape transfers directly. |
|---|---|---|
| Colors and materials | Reduced | ASC can hold per-vertex color and DXF holds one color per object, so materials are flattened to that. |
| Units and scale | Kept | DXF stores an explicit unit, so the model opens at true size without rescaling. |
| Map coordinates | Kept | DXF 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. |
What the DXF writer emits: ASCII R12 DXF, which opens in every AutoCAD release back to 1992. A 3-D model writes each closed body as one polyface mesh, which AutoCAD turns into a solid with MESHSMOOTH and CONVTOSOLID (a solid from a Rhino file over 32,767 faces is simplified to fit; other meshes that large keep every triangle as 3DFACEs), and every other triangle as a 3DFACE, in millimeters and Z-up. A drawing writes LINE, POLYLINE, ARC, CIRCLE, TEXT and SOLID in the drawing’s own units, on layers named after the source layers, with color as the nearest ACI palette index. Georeferenced data (a survey, a map) goes back on its map grid, in the grid’s unit.
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: AutoCAD DXF R12 (.dxf)
The CAD interchange format that opens in everything, back to AutoCAD releases from 1992.
Opens in: AutoCAD, BricsCAD, DraftSight, LibreCAD, QCAD, Rhino, laser and CNC software.
Your file never leaves your computer
Both the ASC parser and the DXF 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.
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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 DXF 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 DXF export?
ASC can hold per-vertex color and DXF holds one color per object, so materials are flattened to that.
▶Will the DXF open at the right size?
DXF stores an explicit unit, so the model opens at true size without rescaling.
▶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 DXF back to ASC?
Not here. We read ASC and write DXF, 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 DXF
Or start from the universal 3D viewer.