Metaflop
Metaflop is a free web application for customizing fonts with Metafont.
What Metaflop is
Metaflop is a free web application for customizing fonts with Metafont. Its Modulator lets you adjust dimensions, proportions, shapes, optical corrections, glyphs, and other parameters using sliders or numeric values, without writing Metafont code. Chart and anatomy previews help inspect the design and understand individual parameters. Metaflop handles repetitive font-generation work in the background. Every change is calculated on its server, which returns a webfont for the preview; speed depends on server activity and your internet connection, and older browsers do not support this preview. Finished fonts can be downloaded as webfont packages or OpenType PostScript fonts. Generated outline fonts use the SIL Open Font License 1.1, while project source code and Metafonts use the GNU General Public License v3.0. The library includes Adjuster, Bespoke, Fetamont, and Funtauna. Drafts are restored through share URLs rather than saved online.
Good
- Free web application
- Slider and numeric font controls
- Webfont and OTF downloads
- Anatomy and chart previews
- Several Metafonts available
Watch out
- No online draft saving
- Cannot download Metafont files
- Preview depends on server and internet
- Older browsers lack preview support
Who it suits
Metaflop suits people designing or modifying typefaces in a browser, especially those who want visual controls instead of Metafont coding. It also fits users needing downloadable webfont or OTF files under the stated licenses.
Verdict
Metaflop combines browser-based typeface controls with automated generation and downloadable font formats. Its share-URL draft recovery and lack of Metafont export are important limitations to consider.
The facts
Each one read from Metaflop's own pages, with the date it was checked.
What it does
- Adjuster character coverage
- MF Adjuster has 256 T1-encoded characters supporting many European languages written in Latin script.checked 9 Oct 2026
- Adjuster design
- MF Adjuster follows a strict grid, uses no curves, and offers a reduced set of parameters.checked 9 Oct 2026
- Automated generation
- Metaflop automates repetitive font-generation tasks in the background.checked 9 Oct 2026
- Download limit
- Metaflop does not support downloading a Metafont file; it points users to the Metafonts’ source code on GitHub.checked 10 Oct 2026
- Downloads
- Generated fonts can be downloaded as a webfont package or an OpenType PostScript font (OTF).checked 10 Oct 2026
- Draft sharing
- Drafts cannot be saved online, but users can copy a share URL and reopen it later to restore a draft.checked 10 Oct 2026
- Font generation
- The Modulator automates repetitive tasks while users adjust typeface parameters.checked 10 Oct 2026
- Font library
- The site offers the Adjuster, Bespoke, Fetamont, and Funtauna Metafonts.checked 10 Oct 2026
- Font licensing
- Generated outline fonts are licensed under the SIL Open Font License v1.1, which the FAQ says allows free download.checked 9 Oct 2026
- Licensing
- Generated outline fonts use the SIL Open Font License 1.1, which permits commercial use and requires derivative works to remain under the same license.checked 10 Oct 2026
- Modulator controls
- The Modulator includes controls for dimensions, proportions, shape, optical corrections, glyphs, and a chart preview.checked 10 Oct 2026
- Parameter preview
- The anatomy preview provides an overview of specific font parameters.checked 10 Oct 2026
- Performance
- Font parameter changes are calculated on the server, and preview speed depends on server activity and the internet connection.checked 10 Oct 2026
- Preview processing
- Each parameter change is calculated on Metaflop's server, which returns a webfont used to render the preview.checked 9 Oct 2026
- Project license
- The project source code and Metafonts use the GNU General Public License v3.0, which allows commercial use subject to its source-sharing terms.checked 10 Oct 2026
- Purpose
- Metaflop is a web application for customizing fonts with Metafont by adjusting sliders or numeric parameters.checked 10 Oct 2026
- Saving drafts
- Metaflop does not support saving drafts online; users can restore a draft by saving and reopening its share URL.checked 9 Oct 2026
- Source licensing
- The project source code and Metafonts use the GNU General Public License v3.0, which allows commercial use under its terms.checked 9 Oct 2026
- Support
- For parameter guidance, the FAQ recommends enabling the Modulator's anatomy preview to see an overview of specific font parameters.checked 9 Oct 2026
- Unsupported export
- The FAQ says Metaflop does not support downloading a Metafont file, though source code for its Metafonts is available on GitHub.checked 9 Oct 2026
- Visual controls
- The Modulator lets users change font parameters with sliders or numeric values without writing Metafont code.checked 9 Oct 2026
Where it runs
- Browser support
- The webfont-based preview is not supported in older browsers.checked 10 Oct 2026
The company
- Makers
- Alexis Reigel is a co-founder and developer, and Marco Müller is a co-founder and designer.checked 10 Oct 2026
- Team
- The About page identifies Alexis Reigel and Marco Müller as Metaflop co-founders.checked 9 Oct 2026
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