BluePlot — Free DXF, DGN & CAD Viewer in Your Browser

Open DXF, DGN, SVG, GeoJSON and KML drawings online in any browser. Measure distance, area and slope. 100% local — files never leave your computer. Free, no signup, works on Mac, Windows and Linux.

What BluePlot does

  • Opens DXF, DGN, SVG, GeoJSON and KML drawings directly from drag-and-drop or a file picker — no install, no signup.
  • Native DGN parser (v7 ISFF and partial v8 OLE2) — you don't need MicroStation, AutoCAD or any desktop software.
  • For DWG files, use the free ODA File Converter to produce a DXF first, then drop it here.
  • Measurement tools: distance, polygon area (Shoelace), and slope from elevation data.
  • Layers, entity info, 2D top-down and 3D orbit view, plus PNG export of the current view.
  • Surveyor's field book overlay: drop a .txt point list alongside a CAD drawing for ČÚZK-style markers on top.
  • Privacy by design: parsing runs locally in WebAssembly + WebGL. Your file is never uploaded.

Who uses it

  • Landowners reviewing a parcel survey from their geodet.
  • Architects and designers who need a quick CAD preview without firing up AutoCAD.
  • Real-estate agents and conveyancers opening a property's cadastral map.
  • Civil engineers and GIS analysts inspecting GeoJSON or KML on the go.
  • Anyone handed a CAD file with nothing to open it in.

Frequently asked questions

Is BluePlot really free?
Yes. No paywall, no trial, no signup. The whole viewer runs in your browser; we don't have anything to sell you on the other side of a login.
Do my CAD files get uploaded to a server?
No. Parsing and rendering happen entirely in your browser using WebAssembly and WebGL. Your file is never sent anywhere — open the page, drop a file, and the network tab stays quiet.
Which file formats does BluePlot open?
DXF (any version), DGN (v7 ISFF + partial v8 OLE2), SVG, GeoJSON, KML, and surveyor's TXT field books. For DWG you'll need to convert to DXF first using ODA File Converter (free, official).
Can I open DGN files without MicroStation?
Yes. BluePlot has its own DGN parser compiled to WebAssembly. You don't need MicroStation, AutoCAD, or any desktop CAD program installed.
Can I measure distances and areas?
Yes — there are tools for distance (two clicks), area (polygon, Shoelace formula), and slope (two elevation points). Values report in the file's native units, including S-JTSK metres for Czech cadastral data.
Does BluePlot work offline?
After the first load, yes — the viewer is a static SPA, so once the page is cached your browser doesn't need network access to open more drawings.
What about DWG files?
DWG is a proprietary binary format with no open spec, so there's no native browser parser yet. Convert your DWG to DXF first using ODA File Converter — it's free, official, and takes two minutes.