What’s the Difference Between Tamari and Soy Sauce—and Does It Matter?

If you've ever wondered about using tamari vs. soy sauce while prepping vegetables for a stir-fry or a dipping sauce for dumplings, then you know these two sauces bear more than a passing resemblance. Perhaps you've even lumped them together as being one and the same. But while each performs miracles of a culinary sort, heightening the deliciousness of countless dishes with just a splash, there is a dotted line between the two. And while tamari and soy sauce can be used interchangeably in recipes—there are a few caveats.

We spoke to Asian condiment experts to learn more about their differences and similarities.

Tamari vs. Soy Sauce

Both tamari soy sauce and soy sauce are fermented soybean condiments (yes, tamari is a type of soy sauce—read on!). Like genies in the bottle, they lend salty-sweet oomph to mains and sides, but several factors, from ingredients to production methods set them slightly apart. "Soy sauce is saltier with a thinner consistency, lighter color, and contains wheat. Tamari is thicker, darker, less salty, and typically wheat-free," says Danny Taing, founder of Bokksu, a snack box subscription service and online Asian market specializing in artisanal Japanese products.

But that's just scratching the surface.

Ancient History

No newcomer to the seasoning aisle, these products have been made and consumed across Asia for over 2,000 years.

Chinese origin: "Soy sauce and tamari soy sauce, known as jiang, is said to have originated in China between the 3rd and 5th centuries," says Andrew Hunter, executive chef at Kikkoman, a Japanese-founded brand known for its naturally brewed soy sauce. A precursor to today's brown liquid, jiang was a thick fermented paste used to preserve foods.

Asian variations: Soy sauce spread from China to Japan and Korea, with different regions developing distinct varieties.

Where tamari comes in: Jiang (or hishio, in Japanese) was introduced to Japan around the Yamato Imperial Court era (250 AD–710 AD). Tamari, Hunter says, was the primitive form of soy sauce. According to one origin story, its discovery was a happy accident: While producing miso, miso makers noticed that the fermented soybean paste released a tasty liquid and dubbed it 'tamari' which translates to 'that which accumulates.'  By the mid-17th century, the process of making naturally brewed soy sauce was rooted in Japan.

Chinese vs. Japanese Soy Sauce

Developed through the ages, soy sauce has innumerable iterations. "Some varieties are more potent or considered higher quality, especially artisanal versions," says Taing. Another key distinction: Chinese soy sauce can be a world apart from its Japanese counterpart.

• Chinese soy sauce:  Ranging from light to dark varieties, some Chinese soy sauces are naturally brewed, while others are chemically produced, containing caramel coloring or additives.
• Japanese soy sauce: The general term for Japanese soy sauce, which combines fermented soybeans and wheat, is "shoyu.' Batches are naturally brewed anywhere from six months to three years.  Below, our focus is on Japanese-style products.

How Soy Sauce and Tamari Are Made

Soy sauce: "Despite its name, soy sauce is not made solely from soy," Hunter says. Steamed soybeans and wheat are used to create koji (soy sauce koji), then saltwater is added. The mixture is stirred, fermented, and aged, then pressed to produce soy sauce.

Tamari: The koji for tamari uses a minimal amount of wheat—or none at all.  For those following gluten-free regimens, it's important to read labels carefully. "There is a common misconception that all tamari sauces are gluten-free, and while many varieties are wheat-free, some contain small amounts of wheat," explains Hunter. Kikkoman's gluten-free tamari, he adds, contains water, soybeans, salt, and sugar.

Color and Flavor

"Both Kikkoman Soy Sauce and Tamari Soy Sauce slowly ferment for months, and this traditional brewing process develops that magical quality everyone loves: umami—the extra boost of savory, mouthwatering flavor known as the ‘fifth taste',” Hunter says. 

Soy sauce: Japan's JAS (Japanese Agricultural Standards) classify shoyu into five types: White shoyu, usukuchi (light shoyu), koikuchi (dark shoyu), saishikomi  (re-brewed and double-fermented shoyu)., and tamari. The color, aroma, umami, and saltiness of each depend on the ratio of soybeans and regional formulations. 

Tamari:  Aromatic and nearly black, tamari uses a higher proportion of soybeans and less saltwater during fermentation, so it has a milder saltiness. Its longer fermentation results in greater umami.

Texture

Tamari is slightly thicker, with more viscosity than soy sauce. Soy sauce's watery consistency makes it better for blending into dishes or sauces.

When to Use Tamari and Soy Sauce

Tamari and soy sauce can be used interchangeably in recipes—with a few caveats. "Tamari's flavor and color make it ideal for recipes that feature robust flavors, like stir-fries and braises," says Hunter. Here are a few other ways to enjoy these products:

• Sashimi: Tamari pairs well with fatty sashimi like tuna or salmon.
• Grilled proteins: Tamari brings a gorgeous glaze to yakitori or teriyaki chicken.
• Marinade: Soy sauce is outstanding in marinades. Try our Soy and Ginger-Marinated Pork Chops.
• Soups: A splash of soy sauce further elevates our Miso Soup With Tofu and Kale.
• Sauces: Tamari's richness lends itself to steak sauce.
• Dipping sauce: Soy- or tamari-enhanced dipping sauces enrobe dunkable bites like pot-stickers.
• Noodles: Udon, ramen, and soba noodles benefit from an umami hit of tamari or soy.

Taste and Experiment

When considering whether to use tamari or soy, our experts suggest you conduct your own taste taste. "I encourage chefs and consumers to taste both tamari and soy sauce and experiment with them as condiments and in cooking," says Hunter. Both are delicious and extremely versatile, he says, so which you use may come down to personal preference.