Combining typefaces is one of the most challenging skills for a designer to master. Setting two fonts together in the same design brings out unexpected flavors in them both. What’s more, there’s rarely a right or wrong answer.
There are dozens of different ways to combine typefaces, some more useful than others, but the most practical place to start is to understand the role of each typeface and to focus on its qualities.
HOW MANY FONTS IS TOO MANY FONTS?
You rarely need more than one typeface. One is almost always adequate to create a hierarchy and convey your message.
In practical terms single typeface design is rare, if only because most designs feature a logo, and most logos feature text, and by its nature a typeface used for a logo will probably not work for body text. There is a rule of thumb that says that you shouldn’t use more than three typefaces in a single design, given that the logo uses one (or two!) typefaces, you’re probably restricted to two faces.
Normally, in order for our headings to stand out when the page is scanned, we use one typeface for body text and one for display. However, you can make headings stand out by using a bold variation, or an accent color, you don’t necessarily need an additional typeface for this.
Font files tend to clock in at around 65kb, if you’re using italic and weight variants then that’s almost 200kb of download added to your site. What’s worse are the additional http requests being made to the server.
So the answer is, the fewer fonts the better. Each typeface has to earn its keep, if you don’t have a good reason for using it, then don’t.