SolveSpace Runs Full 3D CAD in Your Browser

Here's something that slipped under the radar while everyone was arguing about AI coding tools: SolveSpace now runs entirely in your browser.

No install. No account. No cloud subscription. Just open a webpage and start designing parametric 3D models — then download your STEP files when you're done.

This is a big deal for builders.

What Is SolveSpace?

SolveSpace is a parametric 2D/3D CAD tool. It's been around for over a decade as a desktop application, but the team recently shipped an experimental browser version compiled with Emscripten.

Parametric CAD means you define constraints and dimensions, and the software solves the geometry for you. Want a hole exactly 15mm from an edge? Set the constraint. Want to change it later? Update the value — everything adjusts.

It's the kind of tool that used to require a $3,000/year Fusion 360 license or an intimidating FreeCAD install. Now it's a webpage.

Why Builders Should Care

If you're doing anything with physical hardware — 3D printing, laser cutting, CNC, product prototyping — you need CAD at some point. The usual options:

• Fusion 360 — Great, but cloud-dependent, subscription-creep is real, and Autodesk keeps adding restrictions
• FreeCAD — Open source, powerful, but the learning curve is steep (though 1.0+ is much better)
• TinkerCAD — Easy but hits a ceiling fast
• OnShape — Browser-based, but your designs are public on the free tier

SolveSpace slots in as the fastest path from "I need a bracket" to an STL file. One HN commenter put it best:

That's the real value. Not feature parity with SOLIDWORKS. Speed to result.

How the Browser Version Works

The desktop app is compact enough that it compiles down with Emscripten. The result runs entirely client-side — after the initial load, there are zero network dependencies. Your model stays on your machine.

You can even self-host the static files. The build instructions are in the GitHub repo if you want to run your own copy.

It's marked experimental — expect some bugs that don't exist on desktop. But for smaller models, the experience is reportedly "highly usable."

The Tradeoffs (Being Honest)

SolveSpace isn't trying to be FreeCAD or Fusion. It's a focused tool:

• Small kernel (<10k lines of NURBS code vs. 1M+ for OpenCASCADE)
• Constraint-based 2D sketching → 3D extrusion
• STEP, STL, DXF export
• Works on macOS, Windows, Linux, and now the browser

What it doesn't have yet: chamfers, fillets, lofting, or advanced surfacing. The maintainer has chamfers/fillets on the roadmap but acknowledges they're "extremely difficult to do in the general case."

For a quick replacement part or a custom enclosure though? You probably don't need those features.

Who Should Try It

• 3D printer owners who want to design functional parts without learning FreeCAD
• Hardware hackers who need a quick enclosure or bracket
• Hobbyists on a budget who refuse to pay for CAD subscriptions
• Anyone on a Chromebook or locked-down machine who can't install desktop apps

Try It Right Now

Go to solvespace.com/webver.pl and hit "Start Experimental Web Version." You'll be doing parametric CAD in about 30 seconds.

The official tutorials and reference manual are solid starting points. There's also a forum and an IRC channel (#solvespace on Libera Chat).