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Interactive Previewing and Comparing

For end-user documentation see

The lastest release can be downloaded here.

FontGoggles was funded by Google Fonts.

Brief description

FontGoggles is a font viewer desktop app for macOS that supports these file formats:

  • .otf, .ttf, .otc, .ttc, .woff, .woff2
  • .ufo
  • .designspace
  • .ttx

It uses HarfBuzz for line layout, so it supports complex scripts. The source formats are partially compiled on the fly, so their line layout and variation behaviour can be realistically previewed.

When a font file changes on disk, FontGoggles will automatically reload it and show the updated version.

Build instructions

If you want to build and run the app from the source, follow these instructions.

  • Make sure you have Python 3.7 installed, preferably from, but homebrew may work, too. (3.8 may work, but I didn't check whether all our dependencies are available.)

  • Clone this repository.

  • cd into the repository folder.

  • Setup a virtual environment:

    $ python3.7 -m venv venv --prompt=fontgoggles

  • Activate the environment:

    $ source venv/bin/activate

  • Update pip:

    $ pip install --upgrade pip

  • Install dependencies:

    $ pip install -r requirements.txt

  • Install dev dependencies:

    $ pip install -r requirements-dev.txt

  • Install our lib:

    $ pip install .

  • Or, if you prefer an editable install of our lib:

     $ pip install -e .
     $ ./Turbo/

    (The latter step builds a required C library, that otherwise wouldn't get built in editable mode.)

  • Run some tests:

    $ pytest

  • Build the application:

    $ python App/ py2app

You'll find the built application in App/dist/

Now you can drop some fonts onto the app, or a folder containing fonts.