Clam juice is a liquid strained from freshly shucked clams. In some regions, clam juice is made from cooked clams, while others use the liquid from fresh, raw clams. In either case, clam juice has a briny flavor which complements a wide range of dishes. It is often available in bottled form at supermarkets, and in clam producing regions it can be purchased at a harbor or processing center as well.

A clam is a type of bivalve mollusk, found in both fresh and salt water. Clams have been used as a food source for centuries by people all over the world, and the liquid which strains from freshly gathered clams has also traditionally been collected and used in an assortment of foods. Since clams taste best when they are fresh, they are particularly popular in coastal regions of the world, such as the Eastern seaboard of the United States and many Mediterranean countries.

One of the most common uses for clam juice is as a cooking liquid for seafood dishes. Some cooks also use it as a substitute for fish stock, which can get expensive and quite stinky when made at home. A dash of clam juice may also be added to foods for a hint of a briny flavor without an overwhelming sense of seafood. Some savory cocktails also call for clam juice. A popular clam juice product is Clamato, made by the Mott's company. The product combines tomato and clam juices for use as a mixer in drinks.

The meat of clams is sold separately from the juice. Fresh clams may be steamed in clam juice to enhance the flavor of the meat, and canned or preserved clams may also be simmered in clam juice. Cooks who struggle with rubbery preserved clams may want to try only briefly cooking them, as they tend to get very chewy with prolonged cooking. Preserved clams should be thrown into a dish at the last minute and barely warmed, rather than stewed.

One of the most famous dishes along the Eastern seaboard is clam chowder, which purists claim must contain clam juice. For a classic Maine style clam chowder, pan fry one quarter cup of onion in butter in a small saucepan, and add one and one quarter cups of clam juice to deglaze the pan. For a more rich flavor, sauté several strips of bacon with the onion. Add one potato chopped into loose chunks, along with one quarter cup half and half. Simmer until the potatoes soften around 15-20 minutes, adding two ounces (57 grams) of cooked chopped clams at the end to heat briefly, along with salt and pepper. Garnish with parsley and serve with a hearty bread.