Both Campari and Aperol are famous for summertime cocktails due to their bright colours and are traditionally consumed as part of Aperitivo to whet the palate, added into popular cocktails like Negroni and Aperol Spritz.
Today, both Italian bitters, Campari and Aperol, are owned by the Campari Group, but their similarities end there. Here's how they differ:
Origin
The Barbieri brothers, Luigi and Silvio, originally created Aperol in 1919 in the Italian city of Padua. Roughly 145 miles west in Milan, and 59 years prior, Gaspare Campari invented his namesake bitter, Campari, in Novara in 1860.
Colour
Campari and Aperol are associated with summer drinking largely due to their bright colours. Campari is the darks of the two with a vibrant crimson shade that used to be derived from carmine dye though this practice has been discontinued since 2006.
Aperol, on the other hand, has a bright red-orange hue evoking its predominant flavour.
Alcohol content
Campari is bolder when it comes to alcohol content at 20 to 28.5% ABV depending on the country it is sold in. Aperol, on the other hand, ranges from 11 to 15% ABV.
Taste
Aperol is decidedly the more approachable and sweeter of the two.
Both Campari and Aperol have a rich orange sweetness combined with bitter herbal undertones. And easy way to remember their flavour and alcohol content is to remember: the redder the more bitter, the more alcohol content.
A typical sip starts sweet and slowly changes as you begin to distinguish a near-infinite combination of herb and spice flavours, before finally reaching a persisting, pleasant, bitter finish.
Use in Cocktails
Aperol is more commonly found in lighter cocktails like the Aperol Spritz, while Campari with is bold taste is used in bolder cocktails such as the Negroni.
Source(s) - The Garden Barkos, Food and Wine, Vinepair