Kimchi and sauerkraut are fermented cabbage dishes with long histories and which are highly versatile. The fermentation process for both works the same: lactic acid bacteria cause the sugar within cabbage leaves to ferment. The result is that the traditional versions of both share a sour flavor and are highly beneficial for gut health. While these two dishes have ancient roots going back to Asia, they have changed considerably over the last few centuries. The SPICEography Showdown compares their qualities.
Table of contents
How does kimchi differ from sauerkraut?
Kimchi and sauerkraut use different versions of the same main ingredient: cabbage. The most common kind of kimchi and the kind that most people outside of Korea know is made mainly with Napa cabbage. Other kinds of cabbage and various vegetables may be used — there are hundreds of kimchi varieties — but the best-known ingredient is Napa cabbage. Sauerkraut is most often made entirely with the round cabbage that is most common in Europe and the US. It is usually made with the green version but can be made with the red version.
Kimchi 
Sauerkraut
The flavoring ingredients in kimchi and sauerkraut differ as well. Kimchi will often include radishes and intense seasonings like gochugaru (red pepper flakes), fish sauce or raw seafood and ginger. The result is an intense umami character to go with the sourness and spicy heat. While modern versions can include a diverse range of ingredients, traditional sauerkraut is seasoned with salt, though some versions may get a little additional flavor from juniper berries or caraway seeds. The flavor there is primarily sourness with a little saltiness and piny or licorice aroma from the juniper berries or caraway seeds.
Kimchi and sauerkraut may also differ based on how the two cabbages are cut. The Napa cabbage in kimchi is typically cut into large square pieces or may even be left whole in some versions. Sauerkraut is commonly cut into fine, uniform strips.
Kimchi and sauerkraut differ in availability in many places, including many parts of the US where sauerkraut will be far easier to find and less expensive.
Can you use kimchi as a substitute for sauerkraut (and vice versa?)
Kimchi can work as a substitute for sauerkraut in the sense that it will complement the same dishes. Kimchi will provide a sour, savory fermented flavor just like sauerkraut. The big difference will come from the additional flavors that kimchi has. If your dish won’t benefit from spicy heat and the intense umami that the most popular style of kimchi will bring, it won’t be a good sauerkraut substitute. Even if you are using a milder version, kimchi will usually be saltier and have a stronger tartness than sauerkraut, so you should cut down on the portion when using it as a substitute.
Sauerkraut can work as a kimchi substitute, but you should keep its relative blandness in mind. If you are using it as an ingredient in a dish, you can adjust the other seasonings to compensate. For example, you can add some of the spices commonly found in kimchi, like gochugaru and fish sauce. You will also need to increase the salt content and sourness.
When should you use kimchi, and when should you use sauerkraut?
Kimchi is a traditional accompaniment to classic Korean dishes like soondubu jjigae. Sauerkraut is a great condiment and side dish for traditional central European foods including German and Polish pork sausages, but you can also serve it alongside pasta. In the US, it is a traditional hot dog condiment.