Is it Ketchup or Catsup? Here’s the Real Difference

Ketchup has become a wildly popular (some would say ubiquitous) condiment in the United States and beyond. Nowadays, we have an abundance of choices of what to dip our fries into, from dozens of supermarket ketchup brands, to small independent makers, to DIY versions (you could even step outside the box and spice it up.) 

In the U.S. you’re unlikely to come across a bottle labeled anything but “ketchup,” but once upon a time your choices would have included products labeled with the word “catsup.” So what’s the difference? Or are they the same thing? We’ll answer the question once and for all. 

As it turns out, they’re the same thing! Ketchup and catsup are both Westernized terms for a condiment that has origins in China: fish sauce. Ketchup as we know it today is a modernized version of fish sauce, which was made in port towns on the South China Sea with salted and fermented anchovies. The condiment made its way west via European merchants, taking with it Westernized pronunciations. 

Early recipes for ketchup (or catsup, if you like) incorporated a wide variety of ingredients like mushrooms, walnuts, and shellfish (hence the distinction tomato ketchup). Ketchup evolved to include ingredients like vinegar and alcohol (like wine and brandy) that served as both flavor enhancers and preservatives. Today, ketchup has become both sweet and savory with the addition of sugar to our modern versions. 

The tomato-based version we most often see today was developed in the late 1800s, with Heinz introducing its bottled version in 1876. Heinz originally bottled their condiment as “tomato catsup” and changed their branding to “Heinz Tomato Ketchup” soon after bringing it to market in order to distinguish it from competitors. Other brands followed suit once it became clear that “ketchup” was the more popular term among U.S. consumers.