What Is Flounder?

A Guide to Buying and Cooking Flounder

Filets of flounder

The Spruce Eats / Abby Mercer

Flounder is a group of species of flatfish known for their flaky flesh, mild flavor and delicate texture. It can be baked, broiled, fried, sauteed, or steamed.

What Is Flounder?

Flounder is not a specific fish but rather a group of fish, specifically flatfish, that encompass different species and different families, though they all belong to the order Pleuronectiformes. These fish live on the bottom of the ocean, where they lie on their wide, flat bodies, and have both eyes on one side of their heads (either the left or right, depending on the species). Flounder are a medium-sized fish, that can weight from 5 to 30 pounds.

How to Cook Flounder

Flounder is usually sold in fillets, which means there are no skin, bones or excess fat to remove before cooking. Since it's more of a delicate fish that flakes easily, the best ways to cook it are those that make the most of its delicate texture, like baking, broiling, poaching, sauteeing, or steaming. When sauteeing or pan frying, it's not uncommon to prepare a batter, or a coating made of corn meal, for instance, which helps the fish hold together.

What Does Flounder Taste Like?

Flounder is a mild-tasting fish with slight sweetness and a delicate, flaky texture. It's a slightly fatty fish, but not fishy-tasting.

Deep fried flounder on plate with lemon

The Spruce Eats/Diana Mocanu

Flounder Recipes

In addition to recipes such as the ones here that specifically call for flounder, you can generally also substitute flounder for any recipe that call for other flatfish, such as halibut, sole, dab, plaice, turbot, and fluke.

Is Flounder Good for Me?

Many fish are known to contain dangerous levels of mercury, especially larger fish such as tuna, swordfish, shark and marlin. Flounder, however, is a smaller fish, and is considered one of the best choices to eat in terms of mercury levels. The same goes for other flatfish varieties such as sole and plaice, which are sometimes called flounder.

Where to Buy Flounder

Flounder is one of the most widely available fish, and can easily be found in supermarkets, both at the seafood counter and the frozen section. It's usually sold in fillets, but can sometimes be found whole as well. Like most fish and seafood, the frozen version is usually the best quality, since it's typically processed and flash frozen on the fishing boat to capture its peak freshness. Frozen flounder can also be purchased from online retailers. 

Storing Flounder

If you purchase frozen flounder in a vacuum-sealed package, you can store it in your freezer until you're ready to use it. The best way to defrost it is to transfer it to the refrigerator the night before you plan to use it. Flounder that wasn't frozen when you purchased shouldn't be stored, but cooked the day you bring it home. If that's not possible, you should absolutely use it within a day or two at the most.


As discussed earlier, flounder is not the name of a specific species or even family of fish, but rather a somewhat generic name used to describe fish from the flatfish order Pleuronectiformes. Therefore, it's not entirely accurate to speak in terms of flounder varieties. Still, there are a fairly wide variety of fish that are commonly regarded as flounder.

Examples of these are the summer flounder, which is sometimes called fluke, winter flounder, which is sometimes called lemon sole, and southern flounder, all of which are found on the Atlantic and Gulf Coasts of North America.

On the Pacific coast, petrale sole and California halibut are both considered flounder. European flounder, sometimes called white fluke, Dover sole, lemon sole, petrale sole and yellowfin sole are also considered flounder, as is the Greenland halibut, which is also sometimes called Greenland turbot.

Flounder vs. Halibut

One fish that flounder is often compared with is halibut, because they are both flatfish, and because halibut is a popular fish, making it an easy frame of reference for most people. In terms of the fish themselves, one major difference between the two is their size. While a typical flounder might max out at around 30 to 40 pounds, it's not uncommon for halibut to weigh in at 400 pounds or more. When compared with halibut, flounder is less meaty and has a slightly more flaky and delicate texture. Flounder is also fattier than halibut, which is among the leanest fish there is, although flounder is still quite lean and not fishy-tasting.

Article Sources
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  1. Advice About Eating Fish. FDA.gov