SeafoodCheck, previously known as FishToxicity, serves as a convenient pocket guide providing essential information on mercury levels in seafood. It sources its data from the FDA, ensuring reliability. The app targets specific groups such as pregnant women, those planning pregnancy, breastfeeding mothers, and young children, promoting the consumption of fish with lower mercury levels as advised by the FDA and EPA in 2014.

Users can simply input the name of the fish or seafood they intend to consume or purchase to access information on its mercury levels and recommended consumption guidelines. The app's mercury concentration data is sourced from the FDA's "Mercury Levels in Commercial Fish and Shellfish)," while level classifications and consumption guidelines are based on NRDC's "Consumer Guide to Mercury in Fish."