If you've ever worked with CAD files, you know the pain. Someone sends you a .dwg or .dxf file and you either need expensive software to open it or some clunky desktop viewer that takes forever to install.
I ran into this problem constantly — so I decided to build something that solves it.
What I Built
BlinkCAD — a free online DWG and DXF viewer that runs entirely in the browser. No downloads, no signups, just drag and drop your file and it opens.
I built it using Next.js, Three.js for WebGL rendering, and Node.js on the backend. The goal was simple — make it as easy as possible to open a DWG file without installing anything.
Features
Opens DWG and DXF files instantly in the browser
Measurement tools — distances, angles, and areas directly on drawings
Layer toggle — show/hide individual layers
Share with a link — one-click shareable links with optional password protection
Annotation tools — line, rectangle, circle, pen
No signup required — zero friction, completely free
Who Is It For?
Contractors checking blueprints on site, engineers sharing drawings with clients, architects sending files for approval, project managers who just need to quickly view a CAD file. Basically anyone who receives DWG files but doesn't have AutoCAD.
Challenges I Faced
Rendering DWG files accurately in the browser is hard. The DWG format is proprietary and complex — handling all entity types, layer styles, block references, and coordinate systems was a massive challenge. Right now we're at about 85-90% rendering accuracy compared to AutoCAD, and actively working to improve it.
Tech Stack
Frontend: Next.js (React), Tailwind CSS
Rendering: Three.js (WebGL)
Backend: Node.js
Storage: AWS S3 (files auto-deleted within 24 hours)
Hosting: AWS
What's Next
We're working on:
- Improving rendering accuracy toward near-AutoCAD quality
- Adding real-time collaboration features
- Building a sharing system that makes it dead simple to send CAD drawings to anyone
Try It Out
Check it out at blinkcad.com — feedback from developers and CAD users is super valuable to us right now.
If you work with DWG or DXF files, I'd love to hear:
- What features would make this more useful for you?
- What's your current workflow for viewing CAD files?
Thanks for reading! 🚀