Teriyaki sauce and soy sauce look alike, but they are actually different sauces that don’t have the same applications. Look at how they compare to each other in the SPICEography Showdown below.
How does teriyaki sauce differ from soy sauce?
Teriyaki sauce and soy sauce have different origins. Teriyaki sauce came about as a byproduct of the teriyaki cooking technique, which originated in the Edo period that lasted from 1603 to 1868. Some sources claim that teriyaki sauce as we know it is a Hawaiian invention that came from Japanese people who emigrated to the islands.
Soy sauce is thousands of years old. It was most likely invented during the Zhou Dynasty, which lasted from 771 BCE to 256 BCE.
Soy Sauce 
Teriyaki Sauce
Teriyaki sauce and soy sauce have different ingredients. Teriyaki sauce contains soy sauce along with other flavorful ingredients like mirin and sugar. The many variants can include pineapple juice, garlic, and cornstarch for thickening. Soy sauce is made with soybeans as the main ingredient or a mix of soybeans and grain.
The different ingredients in each cause teriyaki sauce and soy sauce to have different flavor profiles. Traditional teriyaki sauce is sweet with intense saltiness and umami, much of which comes from the soy sauce it contains. The Hawaiian version will be a little sweeter with added fruitiness from pineapple juice. Other versions will have added umami from garlic.
Soy sauce is primarily salty with a strong umami character from the glutamates it contains. There are many variations in flavor depending on the style of soy sauce but they all revolve around its salty flavor and meaty taste.
If your recipe calls for one, can you use the other?
Teriyaki sauce only works as a soy sauce substitute if you want to add sweetness to your dish. The sweetness will be valuable for certain types of stir-fry and may be beneficial for marinating some meats, but it won’t be ideal for most dishes that require soy sauce.
Aside from their effect on the flavor profile, sweeteners will affect how quickly a dish caramelizes and may make it more likely to burn in some instances.
Soy sauce works best as a teriyaki sauce substitute if you use it to make your own teriyaki sauce. On its own, it will only supply the color and some of the flavor that you want in a teriyaki dish. The good news here is that all you need is a little mirin and sugar with your soy sauce to get most of the way to a teriyaki sauce.
The best soy sauce to use in place of teriyaki sauce will be a light soy sauce. If all you have on hand is dark soy sauce, you should thin it out with a little water and add some extra salt.
When should you use teriyaki sauce and when should you use soy sauce?
Use teriyaki sauce on any ingredients you want to enhance with a strong umami and sweet flavor, including teriyaki-style dishes. It works best on meats for grilling or in stir-fried dishes. Use thicker teriyaki sauce as a dipping sauce for fried or grilled proteins.
Use plain soy sauce as one of the seasoning ingredients in marinades and dipping sauces. It also works as a condiment for Japanese and Chinese noodle and dumpling dishes.