Opening Fonts

RoboFont can read several file formats.

UFO files

RoboFont can read UFO1 and UFO2 font files.

Opening a UFO can either go by double clicking the file, only if RoboFont is the preferred UFO editor off course :) or drag the file on the app icon or through the ‘Open’ application menu.

Binary font files

RoboFont can read:

  • otf

    OpenType CFF flavored font

  • ttf

    TrueType OpenType font

  • pfa

    PostScript ASCII font

  • pfb

    PostScript binary font

  • WOFF

    Web Open Font Format

  • ttx

    fontTools xml font

  • Font Suitecase

    Extremely Old mac font format

RoboFont will read all glyphs and their corresponding outlines and tries to read the font info.

RoboFont will not read features from .otf and .ttf OpenType fonts.

Python files

RoboFont can be your preferred python editor. It opens all python files (.py) in the scripting window.

A folder with several python files can be dropped on RoboFont’s app icon to open the folder in a scripting window.

Feature files

RoboFont read and writes Adobe Feature files (.fea) natively. Opening a feature file will open a features window. This Window is not attached to a specific font.

To save feature files (.fea) from a font choose “Export Feature” from the file menu (see Application Menu)

Import Warnings

Groups with a ‘ (quote)


RoboFont will warn users when they have groups exported from FontLab with a ‘ (quote) master glyph.

A warning is been printed in the Output Window.


Truetype font or font with quadratic curves


RoboFont can handle quadratic curves but with the limitation there are only two off curve points for each segment. During import RoboFont checks and converts all quadratic segments to two off curves points segments.

The warning sheet can be hidden for future display.

Mixed curve description


RoboFont doesn’t not allow mixed curve descriptions. Mixing bezier curves and truetype splines is in general not a good idea. RoboFont provides a warning sheet that allows users to choose to which curve description they want to change.

Preferred curve description can be set in the Preferences.

Import errors

If something goes wrong during importing RoboFont show a nice traceback. This can either be the UFO is badly written or a font file isn’t readable any more.

Read more: Preferences


It is possible to revert to a save data on disk with ‘revert’. Users can select parts to revert, this ignore other data.