H1-H6 font sizes in HTML

Question

In HTML (and in typography in general, I suppose), there appears to be some defined sizes for H1-H6 -elements.

Ie., if the baseline font size is 16px (or 100%), then h1

Answer 1

One possible progression approach is to use square roots, via a formula such as 2/sqrt[heading#]. Hence, you'd have:

H1 = 2/sqrt1 = 2
H2 = 2/sqrt2 = 1.414
H3 = 2/sqrt3 = 1.155
H4 = 2/sqrt4 = 1
H5 = 2/sqrt5 = 0.894
H6 = 2/sqrt6 = 0.816

For a font base of 12, that'd be close enough to 24, 17, 14, 12, 11, 10. For other bases, the results may be a bit farther away from integers.

Fibonacci would work well with base 16, so you'd have:

H1=32
H2=24
H3=19
H4=16
H5=14
H6=13