7.3.3 Common Markdown Extensions ↑

7.3.3.9 Subscript

As an extension to the original Markdown spec from John Gruber, subscripts are supported, in conformance with the Markdown Guide to Extended Syntax.

To create a subscript, use one tilde symbol (~) before and after the characters.

So that this line…

Every developer's favorite molecule is C~8~H~10~N~4~O~2~.

… will be rendered as follows:

Almost every developer’s favorite molecule is C₈H₁₀N₄O₂.

(Also known as “caffeine.”)

Note that spaces should not be placed within the range of the subscript. H~ 2~O is not water, and neither is H~2 ~O.