When doing some investigation during some recent Headings font work, I noticed that our base typographic rhythm is a bit cramped. I compared against the following:

• Core GB: 16 / 1.8
• Reader (web/mobile): 17 / 1.6
• iOS Reader Mode: 17 / 1.6
• Mobile GB (current): 16 / 1.375
• Mobile GB (proposed): 16 / 1.6 (changed from original post)

For a visual reference, set on a canvas width of 375:

I'm tempted to defer to what Reader web/mobile has in terms of line-height, but considering the base font-size is 16 in our case, the 1.5 line-height ends up being a nice round 24pt, which aligns really well with our 16pt grid and our Block top/bottom margins (12pt).

Update: To align with Reader (web/mobile) and iOS Reader Mode, as well as a slightly more breathable line-height, the new spec should be:

• Base font-size: 16pt
• Base line-height: 1.6

This should also allow for a nice rhythm agnostic to font-size (think dynamic type).

Punch List

• Change base line-height of paragraph text to 1.5 1.6. If we have to define a static px value, let's go with 26. The formula is: (font-size) * (line-height multiplier) = (line-height value), rounded up to the next full point.

Bonus points if we can set up a nice type system that scales well with Lists, Quotes, etc. when we get to those blocks.