Source Sans Pro typeface notes

Table of contents

You can find here my notes for the Source Sans Pro typeface. Source Sans was designed by Paul D. Hunt and is licensed under the SIL Open Font License, Version 1.1.

Opinions & notes

Opinions from the creators and other credible sources. In the end, there are some personal notes.


The design was inspired by American gothics, however, some traits such as the tail on the lowercase l are more reminiscent of humanist typefaces.

The slightly condensed letterforms of Source Sans Pro make it ideal for user interfaces where space is a concern.

A note from Captain obvious: it also has the modulated stroke of the humanist typefaces.

Adobe blog

Source Sans is a classic grotesque typeface with a simple, unassuming design.

In UI screenshots, Source Sans feels more classically typographic than I would expect.

Source Sans on Adobe blog.

My notes

  • Arguably the best and most complete family on Google fonts. Don’t forget that the Source family includes a serif (Source Serif Pro) and a monospace version (Source Code Pro). Additionally, there is an alternative for the monospace version called Hasklig that includes code ligatures.
  • It supports Greek and they are awesome.


All the notes and the interactive controls below are for the variable version of Source Sans Pro; you can see the exact version I used below.

Version 3.006; hotconv 1.0.111; makeotfexe 2.5.65597

A peep at some distant orb has power to raise and purify our thoughts like a strain of sacred music, or a noble picture, or a passage from the grander poets. It always does one good.

OpenType features:

Source Sans Pro supports 52 layout features. It supports features essential for body text, such as old-style numbers (onum), proportional numbers (pnum), small caps, and it also has a ton of stylistic sets and character variants. The following table shows some of the most interesting to me:

Feature codeResultDefaultNotes
ss04 or cv03ggSingle story lower case g
ss05 or cv04llLower case l without a tail.
ss06 or cv05aaDouble story lower case a with a tail
ss02a g la g l

Interesting characters

Many stylistic sets and characters variants. It has a ton of characters U+2000+. For more interesting characters, check the playground or get a copy from GitHub and drop it in the Wakamai Fondue app.

  • M
  • Q
  • S
  • a
  • g
  • l
  • t
  • 💩
  • 🤖

Character support

According to Wakamai Fondue, it has 1436 characters and 2194 glyphs. The font files cover the majority if not all of the following Unicode sets.

Latin Extended-AU+0100-017F
Latin Extended-BU+0180-024Fprobably below 50%
IPA ExtensionsU+0250-02AF
Spacing Modifier LettersU+02B0-02FF
Combing Diacritical MarksU+0300-036F
Latin Extended AdditionalU+1E00-1EFF
Greek ExtendedU+1F00-1FFF
RestU+2000-1F916234 chars!

Not complete sets (below 50%)

Total characters = 17. This means that the typeface supports only specific languages/characters from these Unicode blocks.

Phonetic ExtensionsU+1D00-1D7F14 chars
Phonetic Extensions Supplement:U+1D80-1DBF3 chars

Weights & styles

It has 6 weights with matching italics. It also comes in a variable font format with a weight variation axis that supports weights from 200 to 900.

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