The major problem with these kinds of tool is that they don’t explain why there is any virtue in the scales produced. My answer to that: there is none. Ever. In

The major problem with these kinds of tool is that they don’t explain why there is any virtue in the scales produced. My answer to that: there is none. Ever. In fact, I would go so far as to say that consistent geometric or modular scales like these are normally bad (though I won’t say always), and this kind of consistency actively undesirable, because our eyes and minds just don’t work that way, but value asymmetry and obvious differences in parsing and gathering information. You either end up with insufficient distinction, or grossly excessive variation. That’s why you might do things like this (which I provide as an example of something reasonable, not as the only way of doing things): 1. Page title: positively huge (e.g. 4rem/64px/48pt). Probably not bold (though I freely invite you to use inline styles inside the title, something nowhere near enough people do). 2. Heading: quite large, and with a large gap before it (e.g. 2.5rem/40px/30pt, plus margin-top of 1.5em/60px and margin-bottom of 1rem/16px). Maybe bold, maybe not. 3. Subheading: somewhere between heading and body text in size, and perhaps with a decent-sized gap before it when not preceeded by a heading (e.g. 1.5rem/24px/18pt, margin-top 1.33em/30px and margin-bottom of 1rem/16px). Probably bold. 4. Subsubheading (rare) and certain sorts of captions (e.g. on figures and asides): normal size and distinguished by style instead. (e.g. 1rem/16px/12pt, but bold, and perhaps with a larger gap above.) One thing covered incidentally in this sample scheme is the use of asymmetric margins to visually separate sections. That’s normally a good idea, but for some reason people don’t often try to fit it into their neat mathematical constructions—though you will note this tool’s sample area using such asymmetry unremarked. Probably because their formulæ are arbitrary anyway. Another thing to note is that for general typography you don’t need many levels. As far as major sizes and styles are concerned, I’m sceptical of any general-use model that goes beyond five (title, heading, subheading, caption, body text). As far as headings are concerned, if you’re using more than title + two more, you should probably reconsider your content structure. Cast off the tyranny of typographical scales. They have the appearance of wisdom in promoting rigour, but they are of no value.