Tamari
Top 2 in Top 8 Best Fish Sauce Substitutes
Soy sauce has a kind called tamari. It is made using different ingredients and a different processing method than standard soy sauce. These consist of salt, water, and miso paste made from soybeans. It could also contain a particular kind of brine called moromi and a particular kind of fungus called koji. It has less to no wheat than soy sauce, making it a good alternative for people who are avoiding gluten. Just make sure to check the ingredient list first.
Tamari's increased soy protein level gives it a deeper, bolder, and less salty umami taste than soy sauce. Tamari can be used in place of fish sauce at a ratio of 1:1 or you can start with a little amount and add more to taste.