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Recursive Sans & Mono

Learn more on the Recursive web specimen →

Recursive Sans & Mono is a variable type family built for better code & UI. It is inspired by casual script signpainting, but designed primarily to meet the needs of programming environments and application interfaces.

In programming, “recursion” is when a function calls itself, using its own output as an input to yield powerful results. Recursive Mono was used as a tool to help build itself: it was used to write Python scripts to automate type production work and to generate specimen images, and it was used in HTML, CSS, and JS to create web-based proofs & prototypes. Through this active usage, Recursive Mono was crafted to be both fun to look at as well as deeply useful for all-day work.

Recursive Sans borrows glyphs from its parent mono but adjusts the widths of many key glyphs for comfortable readability. Its metrics are superplexed – every style takes up the exact same horizontal space, across all styles. In this 3-axis variable font, this allows for fluid transitions between weight, slant, and “expression” (casual to strict letterforms), all without text shifts or layout reflow. Not only does this allow for new interactive possibilities in UI, but it also makes for a uniquely fun typesetting experience.

Language Support

Recursive is designed with a modified Google Fonts Latin Expert character set, including numerous useful symbols for currencies & math (see the Character Set notes for more details), plus support for the following languages:

Abenaki, Afaan Oromo, Afar, Afrikaans, Albanian, Alsatian, Amis, Anuta, Aragonese, Aranese, Aromanian, Arrernte, Arvanitic (Latin), Asturian, Atayal, Aymara, Azerbaijani, Bashkir (Latin), Basque, Belarusian (Latin), Bemba, Bikol, Bislama, Bosnian, Breton, Cape Verdean Creole, Catalan, Cebuano, Chamorro, Chavacano, Chichewa, Chickasaw, Cimbrian, Cofán, Cornish, Corsican, Creek, Crimean Tatar (Latin), Croatian, Czech, Danish, Dawan, Delaware, Dholuo, Drehu, Dutch, English, Esperanto, Estonian, Faroese, Fijian, Filipino, Finnish, Folkspraak, French, Frisian, Friulian, Gagauz (Latin), Galician, Ganda, Genoese, German, Gikuyu, Gooniyandi, Greenlandic (Kalaallisut), Guadeloupean Creole, Gwich’in, Haitian Creole, Hän, Hawaiian, Hiligaynon, Hopi, Hotcąk (Latin), Hungarian, Icelandic, Ido, Igbo, Ilocano, Indonesian, Interglossa, Interlingua, Irish, Istro-Romanian, Italian, Jamaican, Javanese (Latin), Jèrriais, Kaingang, Kala Lagaw Ya, Kapampangan (Latin), Kaqchikel, Karakalpak (Latin), Karelian (Latin), Kashubian, Kikongo, Kinyarwanda, Kiribati, Kirundi, Klingon, Kurdish (Latin), Ladin, Latin, Latino sine Flexione, Latvian, Lithuanian, Lojban, Lombard, Low Saxon, Luxembourgish, Maasai, Makhuwa, Malay, Maltese, Manx, Māori, Marquesan, Megleno-Romanian, Meriam Mir, Mirandese, Mohawk, Moldovan, Montagnais, Montenegrin, Murrinh-Patha, Nagamese Creole, Nahuatl, Ndebele, Neapolitan, Ngiyambaa, Niuean, Noongar, Norwegian, Novial, Occidental, Occitan, Old Icelandic, Old Norse, Onĕipŏt, Oshiwambo, Ossetian (Latin), Palauan, Papiamento, Piedmontese, Polish, Portuguese, Potawatomi, Q’eqchi’, Quechua, Rarotongan, Romanian, Romansh, Rotokas, Sami (Inari Sami), Sami (Lule Sami), Sami (Northern Sami), Sami (Southern Sami), Samoan, Sango, Saramaccan, Sardinian, Scottish Gaelic, Serbian (Latin), Seri, Seychellois Creole, Shawnee, Shona, Sicilian, Silesian, Slovak, Slovenian, Slovio (Latin), Somali, Sorbian (Lower Sorbian), Sorbian (Upper Sorbian), Sotho (Northern), Sotho (Southern), Spanish, Sranan, Sundanese (Latin), Swahili, Swazi, Swedish, Tagalog, Tahitian, Tetum, Tok Pisin, Tokelauan, Tongan, Tshiluba, Tsonga, Tswana, Tumbuka, Turkish, Turkmen (Latin), Tuvaluan, Tzotzil, Uzbek (Latin), Venetian, Vepsian, Vietnamese, Volapük, Võro, Wallisian, Walloon, Waray-Waray, Warlpiri, Wayuu, Welsh, Wik-Mungkan, Wiradjuri, Wolof, Xavante, Xhosa, Yapese, Yindjibarndi, Zapotec, Zarma, Zazaki, Zulu, Zuni

License

When you are considering using a font, the font license is one of the first things you should look for and read. It outlines how you agree to use the fonts, and font licensing is different between different type projects & type foundries.

The Recursive project is licensed under the SIL Open Font License v1.1. This is a free software license that permits you to use the font software under a set of conditions. Please refer to the full text of the license for details about the permissions, conditions, and disclaimers.

Using the fonts

1. Download the latest fonts from the Releases (Look under the "Assets" of the latest release, download the zip, and then open that zip)
2. Install the fonts on your system

Installing fonts on your system

Mac

The easy way: open font files in Font Book, and click "Install Font".

The nice way: - In Finder, navigate to the folder <yourusername>/Library/Fonts - Drag this to the Finder sidebar, or while the folder is highlighted, use File > Add to Sidebar to do so - Now, you can manage new font files just like normal files! Drag in fonts. Enclose them in folders to more easily organize families. To deactivate fonts, you can either remove them from this folder or (if you might want them later) right click and "Compress" them into zip files.

Windows

Double-click the TTF file, then select "Install."

To install many static font files (these may work better in apps such as Microsoft Word and PowerPoint): - Go into the static_fonts folder, then into the mono or sans static_otf folder. - Open Font Settings, then drag-and-drop these font files into the Font Settings window.

On the web

This is a big topic, but a couple of good guides are from MDN and from CSS-Tricks.

In general, you should link in the font with @font-face, being sure to use font-weight: 300 1000; to specify the font's weight range:

@font-face {
 font-family: 'Recursive';
 src: url('path/to/font/<UPDATE_SPECIFIC_FONT_PATH>.woff2') format('woff2-variations');
 font-weight: 300 1000;
}

Then, you can use the font with both font-weight and font-variation-settings!

Notes:

• MONO and CASL are "unregistered" axes (not currently in Microsoft's official listing of variation axes and specs), so these tags must be used in all-caps and controlled via font-variation-settings.
• You will eventually be able to also use the property font-style to control slnt and CRSV axes, but these have some browser support issues (as of Oct 2019, but tools are rapidly evolving to better support variable fonts, so this will improve over time!) For now, these work best in font-variation-settings.
• One weird trick: you can use CSS custom properties to more easily control font-variation-settings – read more about this technique in Pixel Ambacht's fantastic tutorial on it.

Font usage in Code Editors

There are two primary ways to use Recursive in code editors:

1: Rec Mono for Code

Install the Rec Mono fonts (found in the “Recursive_Code” folder of release downloads). These have code ligatures & several stylistic sets pre-applied so they will work by default in most code environments & apps. These are also named & configured in a way that enables their use in code themes that utilize italic & bold styles. If you wish to configure specific features in Rec Mono fonts (such as a dotted 0 or single-story g), see Recursive Code Config.

2: Standard Recursive Mono desktop fonts

These fonts are built in a more traditional way than the "Code" fonts above, so they may render slightly better in some contexts. There are pros and cons, though: Code ligatures work better in the "Code" fonts, in many monospace-only apps. On Mac before macOS 11, these do not work in themes with Italic styles – see above for “Code” fonts that do. And, the "Code" fonts allow you a bit more customization, if you want it!

To use the standard decktop fonts, install the desktop Recursive Mono fonts (found in the “Recursive_Desktop” folder of release downloads). Then, activate them & set OpenType features if your code editor allows this. Instructions for three editors follow.

In summary, open the editor settings and set the font family. These family names are shortened because long font names can cause errors in some environments. The main abbreviations are as follows: - Metrics: - Mn means Mono (monospace/fixed-width) - Sn means Sans (proportional/natural-width) - Styling: - Csl means Casual - Lnr means Linear - St means Static (as opposed to variable, like the full Recursive variable font)

So, you will pretty much be setting your editor to use either Recursive Mn Csl St or Recursive Mn Lnr St.

Settings for specific code editors, to use Recursive Mono desktop fonts:

⚙️ VS Code (Click to expand)

In Settings, search Font Family, then specify the family you wish to use.

For Recursive Mono Casual Regular:

"Recursive Mn Csl St", Menlo, "Apple Color Emoji",  monospace

For Recursive Mono Linear Regular:

"Recursive Mn Lnr St", Menlo, "Apple Color Emoji",  monospace

Then, if you want, you can activate OpenType features by searching in the settings for fontLigatures, then editing this in settings.json like this:

    "editor.fontLigatures": "'ss01','ss05','dlig'"

(The above would give you a simplied 6 & 9, a single-story a, and activate code ligatures.)

⚙️ Atom (Click to expand)

In the menu bar, go to Atom -> Stylesheet and add in the following:

atom-text-editor {
  font-family: 'Recursive Mn Csl St';            /* This sets the font family*/
  font-feature-settings: "ss01", "ss05", "dlig"; /* This sets OpenType features, if you want to set them. */
}

Use font-family: 'Recursive Mn Lnr St'; to get the Linear family.

⚙️ Sublime Text (Click to expand)

Go to Sublime Text -> Preferences -> Settings and set font_face to the specific PostScript name of the style you wish to use.

For Recursive Mono Casual Regular:

"font_face": "Recursive Mn Csl St",

For Recursive Mono Linear Regular:

"font_face": "Recursive Mn Lnr St",

To control code ligatures or other OpenType features, set the font_options open, like so:

"font_options": ["ss01", "ss05", "dlig"],

So, the full settings might look something like this:

{
    "font_face": "Recursive Mn Lnr St",
    "font_size": 24,
    "theme": "Adaptive.sublime-theme"
}

Variable Axes

Recursive has the following axes:

Axis Definitions

Axis Definitions, Recursive

• Monospace MONO - 0 to 1. Adjusts the glyph widths from proportional or “Sans” (0) to fixed-width or “Mono” (1).

Recommended use: In general, the proportional design is more readable in text and UI, while the monospace design is more appropriate for code and text in which letter disambiguation is especially critical (e.g. passwords, ID numbers, tabular data, etc).

• Casual CASL - 0 to 1. Adjusts the expressive style or “genre” of the glyphs. In Recursive, this goes from from Linear (0) to Casual (1).

Recommended use: The Linear style shares a similar structure to fonts classified as lineal, merging aspects of humanist sans with rationalized, compact, flat-sided letterforms. This regular, familiar structure makes it appropriate for long-form text requiring focus (e.g. paragraphs, full code documents, and punchy headlines). The Casual style is inspired by single-stroke casual signpainting, but drawn for small sizes. It is most useful in shorter-form text where a warm and inviting tone is desired (e.g. blog post headlines, store signage, and computer terminals).

• Weight wght - 300 to 1000. The overall thickness of letters and the darkness of text composed with them. Notably, in Recursive, the weight axis does not affect glyph width. A bold weight takes the same amount of space as a light weight, even at in proportional styles of the MONO axis.

Recommended use: Differences in weight can provide emphasis in text, show user interaction, or adjust the tone of communication. For light text on dark backgrounds, 400 (“Regular”) tends