Alegreya is a large font family available for free through Google Fonts. It’s by Juan Pablo del Peral of Huerta Tipográfica. Unfortunately, the serif version of Alegreya isn’t yet ready to handle third tones; but at least the sans serif is.
It also comes with complete small caps.
Today’s Pinyin-friendly font is Skarpa, by Aga Silva of Poland. It’s a bit quirky (e.g., second-tone o’s and lowercase q’s) but still sharp.
Skarpa was later modified into Skarpa 2, which is not free but which comes in several weights and types.
Most of Silva’s other fonts also can handle Pinyin with tone marks. Those are all commercial rather than free.
Sherbrooke is a free Pinyin-friendly font by Eyad Al-Samman.
Today’s Pinyin-friendly fonts are Fortunata, which doesn’t quite close the counters of some letters (e.g., a, o, e, p, d), and the somewhat more recent Fortunatus, which does.
Balint Erdosi (I’m sorry to omit the diacritics for now) of Hungary created both of these, which are available as donationware.
Today’s Pinyin-friendly font is another display face: Arca Dashed, by Ricardo Marcin and Erica Jung. It has a papercut style.
The other members of the Arca family, which users may find a bit more serviceable, are commercial.
I shouldn’t go too long without mentioning Google’s ambitious Noto project, which offers both serif and sans-serif versions: Noto Serif and Noto Sans.
When text is rendered by a computer, sometimes there will be characters in the text that can not be displayed, because no font that supports them is available to the computer. When this occurs, small boxes are shown to represent the characters. We call those small boxes “tofu,” and we want to remove tofu from the Web. This is how the Noto font families got their name.
Noto helps to make the web more beautiful across platforms for all languages. Currently, Noto covers over 30 scripts, and will cover all of Unicode in the future. This is the Sans Latin, Greek and Cyrillic family. It has Regular, Bold, Italic and Bold Italic styles and is hinted. It is derived from Droid, and like Droid it has a serif sister family, Noto Serif.
Noto fonts for many other languages are available as web fonts from the Google Web Fonts Early Access page.
Noto fonts are intended to be visually harmonious across multiple languages, with compatible heights and stroke thicknesses.
And it’s free, of course.
Here’s a public-domain script font: Promocyja.
Today’s Pinyin-friendly font is Chispa, by Joan Alegret of La Tipomatica. It’s freeware.