Static fonts specifics

🐓 “Static” fonts is a way of saying traditional, non-variable fonts.

Before going further, make sure you read carefully the overall fonts requirements. And please refer to the requirements about Variable Fonts if you are developping a VF.

Note that GF only onboards OTF-TTF files: .ttf — so TrueType fonts only! The upstream repo can of course contain OTF-CFF .otf fonts, as well as webfonts .woff2. GF redirects users to the upstream repo to find these files if they are not satisfied with the one served by the API.

If the font project consists only of static fonts (and does not include any VF whatsoever), then the statics available upstream will be the main font binaries and will be onboarded. In other cases, statics available in the upstream repository may not get onboarded by GF when:
Background reading:
must→ Overal font requirements

Table of contents

Supported Styles

Google’s static fonts API supports up to 18 styles in one family: up to 9 weights (Thin–Black), + their matching Italics. The table below lists each style’s specific name table and bit settings.

fontmake doesn’t produce Mac names entries any more. If you must add the name for platform 1 (Mac), make sure they are the same as the one in Platform 3 (Windows).

Filename Family Name (ID 1, Win) Subfamily Name (ID 2, Win) Typographic Family Name (ID 16) Typo Subfamily Name (ID 17) OS/2 usWeightClass OS/2 fsSelection head macStyle
FamilyName-Thin.ttf Family Name Thin Regular Family Name Thin 100 bit 6  
FamilyName-ExtraLight.ttf Family Name ExtraLight Regular Family Name ExtraLight 200 bit 6  
FamilyName-Light.ttf Family Name Light Regular Family Name Light 300 bit 6  
FamilyName-Regular.ttf Family Name Regular     400 bit 6  
FamilyName-Medium.ttf Family Name Medium Regular Family Name Medium 500 bit 6  
FamilyName-SemiBold.ttf Family Name SemiBold Regular Family Name SemiBold 600 bit 6  
FamilyName-Bold.ttf Family Name Bold     700 bit 5 bit 0
FamilyName-ExtraBold.ttf Family Name ExtraBold Regular Family Name ExtraBold 800 bit 6  
FamilyName-Black.ttf Family Name Black Regular Family Name Black 900 bit 6  
FamilyName-ThinItalic.ttf Family Name Thin Italic Family Name Thin Italic 100 bit 0 bit 1
FamilyName-ExtraLightItalic.ttf Family Name ExtraLight Italic Family Name ExtraLight Italic 200 bit 0 bit 1
FamilyName-LightItalic.ttf Family Name Light Italic Family Name Light Italic 300 bit 0 bit 1
FamilyName-Italic.ttf Family Name Italic     400 bit 0 bit 1
FamilyName-MediumItalic.ttf Family Name Medium Italic Family Name Medium Italic 500 bit 0 bit 1
FamilyName-SemiBoldItalic.ttf Family Name SemiBold Italic Family Name SemiBold Italic 600 bit 0 bit 1
FamilyName-BoldItalic.ttf Family Name Bold Italic     700 bit 5 + bit 0 bit 0 + bit 1
FamilyName-ExtraBoldItalic.ttf Family Name ExtraBold Italic Family Name ExtraBold Italic 800 bit 0 bit 1
FamilyName-BlackItalic.ttf Family Name Black Italic Family Name Black Italic 900 bit 0 bit 1

If the style name matches the RIBBI convention (ie. ID 2 = ID 17), then name IDs 16/17 are not exported.

In, the Family Name in font info (or the Localised Family Name in the instance), and the Style Name fields are meant to generate the name ID 16/17, or name ID 1/2 if the naming matches RIBBI convention. Although, the export tool can guess it right only if you set the style linking bits correctly as explained below.

Note for OTF-CFF fonts:

Some fonts with a CSS font-weight property of 100 or 200 then the usWeightClass value may be 250, as values of 249 or less in CFF fonts suffered from blurry rendering on older versions of Windows — but in 2020 this is no longer necessary.

Style linking

Several tables in font files need to be set to enable proper style linking between Upright/Italic and Regular/Bold. You can look at the the Open Type spec for more info about the:

The Name table

We strictly follow the RIBBI convention for nameID2 (such as required in the OpenType spec), to allow functional style linking in most environments (button Bold and Italic in desktop apps for example). This means that you can’t have another style name than Regular, Italic, Bold, Bold Italic in name ID 2 (for any platform). Other style name should be appended to name ID 1. The “real” font family name that is impacting how a family is grouped in font menu is handled by the name ID 16 and the “real” style names are in name ID 17.

For projects using, the Style Name field in the set instances will be the one used for the name ID 17. The name ID 2 will be set according to the style linking case and if the style name matches RIBBI. So don’t forget to tick the proper cases: This instance is the [ ] Bold, [ ] Italic of: ___________. You can leave the last field blank which suggests “Regular”, but all other styles need to be mentioned, for example: ExtraLight Italic is [ ] Bold, [X] Italic of: ExtraLight.

Setting up the Italic Angle and ticking the style linking case described above in GlyphsApp should be enough to allow a compiler to set these values correctly.

The following is a summary of the expected values for each style in all the tables mentioned above.


In This instance is the [ ] Bold, [ ] Italic of: ___________


In This instance is the [ ] Bold, [X] Italic of: <Style Name>


In This instance is the [X] Bold, [ ] Italic of: ___________

Bold Italic

In This instance is the [X] Bold, [X] Italic of: <Style Name>

Unsupported styles

If a family has styles which are not in the above table, they should be released as a separate/new family. To do this, append any unsupported style (e.g Condensed) to the family name, so it becomes part of the family name, rather than part of the style name. We frequently use this approach for Condensed and smallcap sibling families. This way, we never have to use name IDs 21/22 for the WWS convention.

For projects which use, you can follow the example of Archivo which contains glyphs files that are set correctly. An additional field Localised Family Name should be added in all concerned instances in order to append the non supported style to the family name and override the one in font info.


Localized Family Name: Archivo Condensed

Style Name: Light Italic

Static font filenames

Font filenames must be based on the following schema:

FamilyName-Style.ttf e.g. Montserrat-Regular.ttf

The filename must not contain anything else.

Remember Google Fonts only allows weight styles, and doesn’t even follow the WWS scheme in the sense that width styles are forbidden and must be part of the family name of the font family:

FamilyNameWidth-Style.ttf e.g. ArchivoExpanded-Regular.ttf

Same for optical size or any other attribute.

Single Weight families

If a family is a single weight and it visually doesn’t have the appearance of a Regular weight, “One” must be appended to the family name and “Regular” used for the style name, since any family must contain a Regular.

This approach allows us to keep the desired font name available if we decide to add more styles in the future: if a future extension of a previously single-weight font includes a Regular, the family name without “One” is used and the “Regular” style name can be given to the new actual Regular weight.

We have released many of these families in the past.

The single weight families must have the following font specific settings:

Filename Family Name (nameID 1) Subfamily Name (nameID 2) Typographic Family Name (nameID 16) Typo Subfamily Name (nameID 17) OS/2.usWeightClass OS/2.fsSelection hhea.macStyle
FamilyNameOne-Regular.ttf Family Name One Regular     400 bit 6  


Static fonts should be hinted using the latest version of ttfautohint. If the results look poor on Windows browsers, it’s better to release the fonts unhinted with GASP table set to “grayscale / symmetric smoothing” (0x000A) across the full PPEM range. ttfautohint often struggles to hint display or handwritten typefaces.

If you don’t use gftools builder (which autohint static fonts by default but you can turn off that option), you should run the fonts through gftools fix-hinting once the fonts have been hinted. If the fonts are unhinted, run the fonts through gftools fix-nonhinting.

Fontmake does not support manual hinting from Glyphs. You can use use VTT instead and you can patch a VTT program with gftools builder — see Montserrat as an example.

You can view the name tables using these tools:

Some font testing web pages allow you to view a selection of tables:

Further reading:
must→ Variable fonts specifics
must→ Vertical metrics
must→ QA - Local testing
learn Build the fonts