Open Source Font Licenses: OFL, Apache 2.0, and Creative Commons

What Is an Open Source Font?

The phrase "open source font" carries two distinct meanings that are often confused. First, the source files for the font, typically in formats like Glyphs, FontLab, or UFO, are publicly available so anyone can study, modify, and improve the design. Second, and more practically relevant for most users, the license attached to the font grants broad rights to use, redistribute, and often modify the font without paying a fee or asking for permission.

This is a meaningful distinction from fonts that are simply "free to download." A font can be free to download while still being restrictively licensed. Plenty of fonts on popular download sites are labeled free but prohibit commercial use, redistribution, or embedding. Those fonts are freeware, not open source. Open source means the license is genuinely permissive in a legally specific way, and the terms are usually based on one of a handful of established licenses that are well-understood by the design and development communities.

Most Google Fonts are open source. Every font in the Google Fonts catalog is licensed under either the SIL Open Font License or the Apache 2.0 license, both of which allow commercial use, web embedding, and redistribution without fees or attribution in your final product. This is why Google Fonts has become the default starting point for many web projects: the licensing is clear, consistent, and genuinely permissive.

Open source fonts also exist outside of Google's catalog. Fonts from repositories like GitHub, Font Squirrel's "100% Free" category, and dedicated foundries like Omnibus-Type or Production Type release many of their typefaces under open licenses. The key is always to verify the specific license, because even among open-source fonts, the details matter significantly.

The ecosystem of open source typography has expanded dramatically over the past decade. Variable fonts, color fonts, and typefaces covering non-Latin scripts are now routinely released under open licenses. For developers and designers who build globally, this means it is increasingly possible to build a complete, professional, multilingual typographic system entirely from open-source fonts without paying a single license fee. Our guide to font licensing for web designers shows how to incorporate open-source fonts into a professional workflow from the start.

SIL Open Font License (OFL) Explained

The SIL Open Font License, maintained by SIL International, is the dominant license in the open source font world. If you pick a font at random from Google Fonts or GitHub, there is a very good chance it is OFL. The license was designed specifically for fonts, which makes it far better suited to typography than general-purpose licenses like the MIT or GPL. It balances genuine openness with protections that matter to typeface designers. For a detailed look at what the OFL permits when modifying or forking a font file, see the guide to font modification rights under the OFL.

The OFL grants you four core freedoms: you can use the font in any project, including commercial work; you can study and modify the font's source files; you can redistribute the font to others; and you can distribute modified versions. These rights apply without paying anything and without needing to contact the author. For a web developer or designer, the practical upshot is that you can drop an OFL font into any project, embed it in your website, bundle it in an app, or ship it in a print design without asking anyone.

The Reserved Font Name (RFN) clause is the part of the OFL that most often catches people off guard. When a font designer releases a font under the OFL, they can declare the font's name as "reserved." If you modify that font and distribute the modified version, you must give it a different name. You cannot call your modified version "Roboto" or "Inter" if those names are reserved. This protects the original author's reputation while still allowing the broader community to build on their work.

The prohibition on selling the font standalone is another OFL-specific rule. You can sell a piece of software, an app, a website template, or a design that uses the font. You can even sell a bundle of tools that includes the font. What you cannot do is sell just the font file itself as the product. This clause exists to prevent commercial exploitation of the font design specifically, while keeping the font accessible as a component of broader creative work.

For web developers, the OFL's copyleft requirement for derivatives rarely applies. Embedding a font in a website does not create a derivative work of the font. Subsetting a font for performance optimization is permitted and does not require relicensing. The copyleft clause only triggers when you modify the font's actual glyph designs or technical tables and then distribute those modified font files.

Attribution is not required in your final product under the OFL. You do not need a credit line in your website footer or in your app's about screen. However, if you redistribute the font files themselves, such as including them in a GitHub repository or a downloadable project template, you must include the original copyright notice and the full OFL license text alongside the font files.

Apache 2.0 License for Fonts

The Apache 2.0 license was originally created for software projects and is used by fonts that want maximum permissiveness. When applied to fonts, Apache 2.0 is noticeably more permissive than the OFL in several ways. Understanding these differences matters when you are building tooling, font bundles, or commercial font products based on open-source foundations.

The most significant difference from the OFL is that Apache 2.0 has no copyleft requirement. If you create a derivative font under Apache 2.0, you can release that derivative under any license you choose, including a proprietary commercial license. You can modify the font, rename it, and sell it as a paid product. This is explicitly not allowed under the OFL, which requires all derivatives to remain under the OFL. For the practical implications when using Google Fonts specifically, our Google Fonts license guide explains which fonts use Apache 2.0 versus OFL and what that means for derivative work.

Apache 2.0 also has no Reserved Font Name concept. You can name your derivative anything you like without worrying about conflicting with the original designer's protected name. There is no restriction on selling the font as a standalone product either. This makes Apache 2.0 the font license of choice for projects that want to maximize reuse and commercial flexibility.

Attribution under Apache 2.0 is required in certain contexts, but the rules are more nuanced than a blanket credit requirement. You must include the original copyright notice, the Apache 2.0 license text, and any NOTICE file included by the original author when you distribute the source form of the font, meaning the font files themselves. However, in the "object form" of distribution, which covers your compiled website, app binary, or finished design, attribution is not required. This means you do not need a credit line in your website or app simply because you are using an Apache 2.0 font.

Practically speaking, for most web development work, Apache 2.0 and OFL fonts behave almost identically. You embed them via @font-face, you do not need to display attribution in your product, and commercial use is unrestricted. The differences only surface when you are redistributing font files, creating derivative fonts for distribution, or building commercial font products on top of open-source foundations.

If you are evaluating which license to use when releasing your own font, the Apache 2.0 choice signals maximum openness and commercial flexibility. The OFL choice signals that you want the typeface to remain in the open-source ecosystem even as it is improved and modified by others. Both are legitimate goals; the choice depends on your priorities as a type designer.

Creative Commons Font Licenses

Creative Commons licenses are widely recognized and frequently misunderstood in the context of fonts. The CC suite was designed for creative works like photographs, illustrations, and written content, not specifically for software or fonts. This creates some edge cases when applied to typefaces, but many font designers have released their work under CC licenses, so understanding the different variants is essential.

The most important thing to understand about Creative Commons is that the name refers to a family of licenses, not a single license. Saying a font is "Creative Commons licensed" without specifying the variant tells you almost nothing about what you can actually do with it. The variants range from complete public domain dedication with zero restrictions all the way to non-commercial only, which prohibits any commercial use at all.

Creative Commons licenses were not designed for fonts, and this shows in several edge cases. The CC licenses do not specifically address subsetting, format conversion, or web embedding. They also do not have a concept equivalent to the OFL's Reserved Font Name. For these reasons, many legal experts in the type industry recommend sticking to OFL or Apache 2.0 for font projects when possible, and using CC only when a font designer has not provided an alternative.

When you encounter a font released under a CC license, always check the exact variant. Look for the license code, which appears in the format CC BY, CC BY-SA, CC BY-NC, CC BY-NC-SA, CC BY-ND, or CC0. Any variant containing "NC" (NonCommercial) or "ND" (NoDerivatives) imposes significant restrictions that may make the font unsuitable for professional and commercial work.

Public Domain Fonts

Public domain is not a license but a legal status. A font enters the public domain when its copyright has expired, when the creator has explicitly waived their rights, or when the work was never eligible for copyright protection. Once a font is in the public domain, anyone can use it for any purpose with no restrictions and no requirements for attribution or licensing compliance.

The most practical way to dedicate a new font to the public domain today is to use the CC0 legal tool, described in the Creative Commons section above. CC0 is a formal, legally robust mechanism for waiving copyright worldwide. Simply writing "this font is public domain" in a README file does not carry the same legal weight because informal declarations may not be enforceable in all jurisdictions.

For historical typefaces, public domain status is genuinely complicated. Copyright terms vary by country, and the font software itself may carry different copyright protection than the underlying letterform designs. In the United States, copyright generally lasts for the life of the author plus 70 years, so typefaces designed before the 1920s may have expired copyrights. However, a digital font file is software, and a modern digitization of a centuries-old letterform is a new copyrightable work based on how the outlines were drawn, optimized, and kerned.

Several repositories actively curate public domain and CC0 fonts. The Open Font Library and certain GitHub repositories maintain collections of fonts with verified public domain status. Font Squirrel's "100% Free" filter includes fonts verified for commercial use, though this does not necessarily mean they are public domain. It means their licenses permit commercial use without fees.

For design work that requires maximum legal certainty with no attribution obligations, CC0 and OFL fonts are the gold standard. CC0 because there are absolutely no restrictions, and OFL because it is well-understood, was designed specifically for fonts, and has been widely adopted by the professional type community. Both represent a level of legal clarity that vague "public domain" claims often do not provide.

If you find a font where the licensing status is genuinely unclear, treat it as commercially restricted until you can verify otherwise. The risk of using an unlicensed font far outweighs the benefit of any individual typeface. With the breadth of genuinely open-source fonts available today, including extensive serif, sans-serif, display, and monospace options at professional quality levels, there is rarely a need to reach for a font with ambiguous licensing.

License Comparison Table

The following table summarizes the key permissions and restrictions for the five most common open-source and free font license types. Use this as a quick reference when evaluating a font for a specific use case. To verify the embedded license metadata of any font file directly, use our font license checker tool.

One dimension not captured in the table is how well each license handles the specific realities of font file distribution. The OFL addresses fonts directly, covering concepts like Reserved Font Names, format conversion, and the distinction between font software and font output. Apache 2.0 and Creative Commons licenses were written for broader categories of content and software, so edge cases in font-specific scenarios may require careful legal interpretation.

For the vast majority of design and development projects, the practical difference between OFL, Apache 2.0, and CC0 fonts is negligible. All three allow you to use the font commercially, embed it on a website, bundle it in an app, and distribute your finished product without fees or visible attribution. The differences matter primarily when you are building on top of fonts to create new typefaces, distributing font files as part of a toolkit or template, or making legal compliance decisions for a large organization with formal IP review processes.