Some awesome typographical rules which will help you ace the game of web development like a ninja. Follow these rules and make your user comfortable and happy.
1. Line height(in pixels) ÷ body copy font size(in pixels) = 1.48
1.5 is commonly used in classic books or novels, we follow this thumb rule. There are very few websites using anything less than this. But all across the web 1.48 is the standard value which makes your content look stable and readable.
2. Line length(pixels) ÷ line height(pixels)=27.8
The average line length is 538.64 pixels(excluding padding and margin), which is quite large considering that many websites still have body which 12 to 13 pixels of font-size.
3. Space between paragraph(pixels) ÷ line height (pixels) = 0.754
The paragraph spacing i.e space between the last line of one paragraph and the first line of the next paragraph rarely equals the leading(which is the main characteristic of perfect vertical rhythm). More often, paragraph spacing is 75% of paragraph leading because leading usually includes the space taken up by descenders and because most characters do not have descenders, additional white space is created under the line to create a perfect design for readers. White space improves comprehension i.e it de-clutters a page by giving items room to breath.
4. Optimal number of character per line is 55 to 75
If we look at classical typographical books, the optimal number of characters per line is between 55 to 75, but between 75 and 85 characters per line is more popular in practice. The appropriate number of characters in a line helps user to read more without loosing focus as well as it is comfortable for eyes to read with least possible movement of eye ball.