THE_GAME_MASTER recently asked me: Are fonts from https://fonts.google.com/ public domain?

Good question! The answer is technically "No"... but they are free and open source! :)

From https://fonts.google.com/about "...All the fonts in our catalog are free and open source, making beautiful type accessible to anyone for any project..."

Seems like Public Domain, but not quite:

"Q: Can I use these fonts commercially: to make a logo, for print media, for broadcast, ebooks, apps, or sewing machines and apparel?

A: You can use these fonts freely in your products & projects - print or digital, commercial or otherwise. However, you can't sell the fonts on their own. This isn't legal advice, please consider consulting a lawyer and see the full license for all details.

This means you can use the fonts in your projects and distribute the font files in your games, even commercial ones, but you cannot license the font files by themselves as CC0 or any other license here on OGA, since that implies the files themselves can be resold. However, to the best of my knowledge, any artwork that features the typeface of a google font can be sold or shared here on OGA. For example: share/sell langar.ttf? Not allowed. Share/sell a graphical User Interface where the images of button text is from langar.ttf? Yep, that's allowed so long as the langar.ttf file itself is not included.

About 99% of the google fonts are under the SIL Open Font license. The other 1% appear to be under the Apache license. Here is the info page for each of the font's attribution and license: https://fonts.google.com/attribution

TL;DR: You can use the fonts in your projects, even commercially. You can not share the font files themselves here on OGA. Art you've created that used the fonts can be shared here on OGA.