Finding high quality screen fonts that look good at all sizes has always been a problem for software designers. But maybe not for long. Inter UI is a set of free open source fonts specifically designed for maximum sharpness and readibility on computer screens. It works well for English and other languages that use either Latin or Cyrillic character sets, though keep in mind that it's not yet in a finished state.
Inter UI was developed by Rasmus Andersson. He started the project in 2016, and it's since gone through two iterations - with the first one failing because the pixel-aligning nature of the approach he used made it difficult to read large blocks of text. The current approach uses more variation in styling to make text more readible.
Inter UI has been released under a SIL Open Font 1.1 licence, and you are free to use the fonts for any application, including commercial ones. You can also freely bundle the fonts with any software.
Inter UI comes in 4 weights: regular, medium, bold and black. Each weight further has an italicized option.
One of the strengths of the fonts is that they have custom settings. These settings include:
Contextual Alternatives Tabular Numbers Slashed Zeros Fractions Open Digits Case Alternatives Localized Forms Numerators Denominators
You can enable or disable these settings by using the CSS command font-feature-settings, and you can see examples of these settings at the project's website.
To use Inter UI, simply download the fonts from their website and host them on your own. You can also import them using the following CSS code:
font-family: 'Inter UI', sans-serif;Contributions
Inter UI is actively seeking contributors. For more information see their GitHub page.
If you need support, you can contact Rasmus Andersson over Twitter (@rsms), or at the email address listed on the project's website.