Numbers appear on top of each other in all manner of contexts, from sports scores to menus to those incomprehensibly dry data tables at the back of academic papers which you always wish would be graphs instead. But it doesn’t matter: no matter the context, you always need to use tabular figures.

Tabular figures are a bit like riding a bike. Once you know about them, you’ll never forget, and you’ll harbor a desire to use them at every opportunity. But in reality you’ll do so much less frequently than you’d like.

For a fantastic introduction to tabular figures, go here, for Jonathan Hoefler’s crystal-clear explanation of how important they are and also how type designers have really thought of everything. But the short version is, simply: Tabular figures are numbers (1, 2, 3…) which all take up the exact same amount of horizontal space, even if they’re in bold or italics or both. Pretty much any time you’re using numbers outside a regular sentence, you should be using tabular figures. And, chances are, you’re not.

Hoefler has tried to rectify this a little bit with his set of office fonts, where all figures are tabular by default, but, well, you’re not using one of those fonts. And whatever font you are using, it probably has tabular figures if you look hard enough, but you don’t know how to look, and in any case they’re probably only part of a “pro” version of the font which you don’t have access to.

Some of the blame here lies with the low-level innumeracy of most graphic designers, although I should note that the latest versions of Microsoft Word have been pretty good about defaulting to tabular figures. Still, because you guys are special and numerate, you’ll understand my favorite reason why tabular figures are so important. Which is Benford’s Law.

Basically, in most fonts, most numerals are pretty much the same width, and there’s a good chance you wouldn’t be able to tell the difference between tabular and normal figures — if it wasn’t for the pesky number 1, which is typically significantly narrower than all the others. And, wouldn’t you know it: The number 1 is the most significant digit about 30% of the time. The most significant digit is, naturally, the one that people pay the most attention to, so it feels off when it’s not properly aligned with the numbers below it.

So, next time you’re putting a table on the internet, remember the magic words. I’ll leave them here, so you don’t forget:

font-feature-settings: 'tnum';