Free, open-source surfboard CAD

Design surfboards,
right in your browser.

Draw outlines, rocker and cross-sections, watch volume and weight update as you go, and export files you can actually build from — STEP, STL, DXF and 1:1 printable PDF. Free and open-source. Nothing to install, nothing to sign up for.

Open the design app View source

FREE · OPEN-SOURCE (GPL-3.0) · STEP · STL · DXF · 1:1 PDF

FIG.01 — SHORTBOARD 5′8″LIVE

5′08″

Length: 5′08″
Width: 19¾″
Thick: 2¼″
Volume: 28.4 L

What it does

Everything you need to take a board from idea to blank.

Outline, rocker & cross-sections

Draw the planshape, tune the rocker, and sculpt rail-to-rail cross-sections with bézier control points — the three views every shape is built from.

Live volume & weight

Volume in litres and an estimated blank weight update as you shape, so you can dial a board to your weight and ability without guesswork.

Real-time 3D preview

A lofted 3D model rebuilds as you edit. Spin it, check the foil, and catch problems before they reach foam or timber.

Export STEP, STL, DXF & PDF

Send a STEP solid or an STL mesh to CAM software, DXF outlines to a cutter, or print 1:1 PDF templates and shape it by hand.

Works offline

Install it once and the editor keeps working with no connection — on a plane, in the shaping bay, anywhere the wi-fi gives up.

Free & open-source

Every feature and every export format is free. The source is on GitHub under the GPL-3.0 — read it, fork it, build on it.

How it works

Three views, one shape.

Sketch the outline

Start from a template or a blank, then pull the curve to your length, width and tail.

Refine rocker & rails

Adjust the rocker profile and cross-sections while volume and weight track every move.

Export & build

Send G-code-ready geometry to a CNC, or print templates and shape it by hand.

Who it's for

Built for people who make things.

Whether you're gluing up a hollow timber frame or roughing out your first PU blank, OpenShaper gives you the numbers and the shape before you commit a cut.

The story behind the project →

Backyard & garage shapers cutting their first blanks
Hollow-wooden & timber builders planning frames and panels
Students and tinkerers learning how board design works
Working shapers who want a free second tool for quick ideas

Learn the craft

New to board design?

Guide

Surfboard design explained

Outline, rocker, rails, foil, volume and fin setups — what each one does and how it changes the way a board rides.

Construction methods compared

PU/PE, EPS/epoxy, hollow wooden, chambered and more — weight, feel, durability, cost and how to build each.

Surfboard volume calculator

Enter your weight and ability for a litre range, see the full volume chart, and learn what shifts the number.

Build a hollow wooden surfboard

The skin-on-frame method step by step — from CAD templates to frame, skins, rails and a proper vent.

Frequently asked questions

Is OpenShaper really free?

Yes — completely. It's open-source under the GPL-3.0 with no paywall, no tiers and no account. Read why.

Do I need to install anything?

No. It runs in any modern browser. There is also an optional desktop build.

Can I use it to drive a CNC machine?

Export STEP or STL for CAM software and 3D printers, DXF outlines for a cutter, or 1:1 PDF templates for hand-shaping. See the construction guide.

Where is my design stored?

In your browser, plus whatever you save or export. Clearing your browser's site data clears saved boards too, so export a .board.json for anything you want to keep.

Design your next board

Open the editor and start shaping — free, in your browser, nothing to install.

Open the design app Read the design guide

Design surfboards,right in your browser.