# Source Serif 4 font > A transitional serif by Frank Grießhammer that partners Source Sans, with weight and optical size axes. Source Serif 4 is a transitional serif typeface designed by Frank Grießhammer for Adobe as the companion of the Source Sans family. Source Serif 4 is a variable font with a weight axis from 200 to 900 and an optical size axis from 8 to 60, with italics. It is released under the SIL Open Font License 1.1. ## Facts - Classification: [Serif](https://trendhub.net/fonts/category/serif) - Designed by: Frank Grießhammer - License: SIL Open Font License 1.1 (https://openfontlicense.org/open-font-license-official-text/) - Styles: 16 (ExtraLight 200, Light 300, Regular 400, Medium 500, SemiBold 600, Bold 700, ExtraBold 800, Black 900; with italics) - Variable font: Yes (wght 200–900, opsz 8–60) - Glyphs: 1463 - Character sets: cyrillic, cyrillic-ext, greek, latin, latin-ext, vietnamese - Last updated: 2025-09-11 - Official source: https://fonts.google.com/specimen/Source+Serif+4 - Page: https://trendhub.net/fonts/source-serif-4 - Tagged for: Headlines, Body text, Editorial ## About Source Serif 4 Source Serif 4 is a serif family in the transitional style, made to accompany Source Sans by matching its letter proportions and the grey value of its text. The official notes say it is loosely based on the work of the eighteenth-century punchcutter Pierre Simon Fournier and keeps some of his quirks, such as the serif at the foot of the b and the middle serif of the w, while simplifying the shapes for digital use. Frank Grießhammer designed it, and Robert Slimbach consulted on the design. The family is a variable font with two axes: weight from 200 to 900 and optical size from 8 to 60, with a default of 20. Eight named weights, ExtraLight to Black, come in roman and italic, 16 styles. The fonts hold 1,463 glyphs covering Latin, Latin Extended, Vietnamese, Cyrillic and Greek. ## License SIL Open Font License 1.1. © 2014 - 2021 Adobe Systems Incorporated (http://www.adobe.com/), with Reserved Font Name ‘Source’. Allowed: - Use the fonts in personal and commercial work, in print, on the web and in apps. - Modify the fonts and build new versions from them. - Redistribute the fonts, on their own or bundled with software, as long as the license text and copyright notice go with them. Conditions: - The fonts cannot be sold by themselves. - A modified version must stay under the same license and cannot use a Reserved Font Name without the copyright holder's permission. - The authors' names cannot be used to promote a modified version without permission. Summary only, not legal advice. Full text: https://openfontlicense.org/open-font-license-official-text/ ## Where it works - **Long-form reading**: The design aims at extended text on paper and screen, and the optical size axis thickens fine details as type gets small. - **Headlines from the same family**: At the upper end of the optical size axis, up to 60, the serifs and hairlines sharpen for titles. - **Serif and sans systems**: Proportions matched to Source Sans let the two alternate between body text and captions without a jump in size or colour. - **Academic and book typography**: Roman and italic in eight weights cover text, emphasis, headings and notes; Greek and Cyrillic serve citations. - **News and magazine sites**: SemiBold to Black set article headlines above text in Regular. ## Things to know - **Optical size from 8 to 60**: The axis default is 20. Browsers apply optical sizing automatically; elsewhere set it by hand. - **Two variable files**: Roman and italic are separate files, each with both the weight and the optical size axis. - **Details taken from Fournier**: The foot serif on the b and the middle serif on the w are deliberate historical features, not errors. ## FAQs ### Is Source Serif 4 free for commercial use? Yes, under the SIL Open Font License 1.1. Source Serif 4 may be used in client and commercial work, embedded, modified and redistributed; it cannot be sold on its own, and a modified version stays under the same license. Check the license text for the exact terms. ### Who designed Source Serif 4? Source Serif 4 was designed by Frank Grießhammer for Adobe. According to the official notes, Robert Slimbach consulted on the design. ### How many weights does Source Serif 4 have? Source Serif 4 has eight named weights, from ExtraLight 200 to Black 900, each with an italic, for 16 styles. ### Is Source Serif 4 a variable font? Yes. Source Serif 4 is a variable font with a weight axis from 200 to 900 and an optical size axis from 8 to 60. ### Which languages does Source Serif 4 support? Source Serif 4 includes the letters needed for English and other Latin-script languages such as German, Polish, Romanian and Vietnamese, and for Russian, Ukrainian, Bulgarian and Greek. ### What fonts pair well with Source Serif 4? Source Serif 4 was designed to complement Source Sans, so Source Sans 3 is its intended partner for headings, captions and interface text. --- Source: https://trendhub.net/fonts/source-serif-4 (trendhub)