GoShawk Extension

Capture Go board diagrams from any webpage and convert them into SGF or HEN format - directly in your browser.

GoShawk Extension screenshot showing a Go board capture

Features

Visual Capture

Click the extension icon, drag to select any area of the page, and GoShawk snapshots it instantly.

SGF & HEN Export

The captured image is analyzed and the board position is reconstructed as SGF or HEN format, ready to use.

Cross-Browser

Supports both Chrome (Manifest V3) and Firefox (≥ 115) with native builds for each platform.

100% Private

Everything runs locally in the browser. No image is ever uploaded or sent to an external server.

How It Works

1

Activate

Click the GoShawk toolbar icon on any page containing a Go diagram. The page dims and a crosshair cursor appears.

2

Select

Drag to draw a rectangle around the board image you want to capture. Press Esc to cancel.

3

Capture

GoShawk crops the selection using the Canvas API (respecting device pixel ratio) and opens a new tab with the SGF/HEN converter pre-loaded with your screenshot.

4

Export

Use the converter to adjust intersections, verify stone placement, and export the final position as SGF or HEN.