“Metaflop.com” is a web application for parametric fonts, designed as a user-friendly tool for the modulation of Metafonts.

Metafont is a powerful and sophisticated description language for vector fonts. It was devised by Donald Knuth in the late 1970's as a counterpart to his TeX typesetting system, to produce high-quality bitmap fonts with the help of mathematical equations. However, unlike its companions TeX and LaTeX that are still widely used for scientific publishing, Metafont has remained in the shadow and even experienced TeX/LaTeX users rarely know about it. It is often regarded as too difficult to use, too arcane and documentation about it is scarce.

Metaflop enables users to easily create their own Open Type fonts based on Metafonts. For this purpose the typographical parameters can be modified either with slide bars or numerically. An automatic preview simultaneously displays the results of the chosen modulation. Users do not have to work with complex font editors nor do they need to grapple with the abstract description language of the Metafont or with the design of individual letters. The repetitive adjustments of the font characters are all completed by the server. This enables the user to focus on the visual output – adjusting the parameters of the typeface to ones own taste. The new fonts can be installed on all current computer systems or linked in as a web font with any website.

Metaflop is a digital program distinguished for its practicality and user-friendliness which may help to popularize parametric type design. While the project serves as a source of inspiration for professional designers it also encourages the general public to experiment with typography and modulate their own fonts. Metaflop fonts were used by design groups and individuals such as Metahaven, Julia, Warriors Studio, Hato, Tsto or Fraser Muggeridge.

Metaflop is an open-source project. All of the source codes and documentation can be found on github. The Metaflop fonts are covered under the SIL open font license which means they are free for any use.

The parametric type design project was supported by the TeX Development Fund. It was amongst the nominees for the Swiss Design Awards in 2012 and the Design Prize Switzerland, Edition 2015/16. Marco Müller and Alexis Reigel, with contributions from Linus Romer and Simon Egli, 2012–2017