Difference Between Clam and Cockle (With Table)

In terms of the habitat of each, clams are usually found closer to the sea shore, while cockles are commonly found scattered on the seabed in significant abundance. This seminal difference is further exemplified in the other dissimilarities embodied by these two varieties of mollusks.

Clam vs Cockle

The main difference between clam and cockle is that the former variety of mollusk is found in both freshwater and saltwater reservoirs, while the latter category of mollusks occurs solely in the briny water bodies around the world. The natural habitat of these two varieties of bivalve mollusks is quite contrary to each other.

Clams can thrive in both types of water bodies. However, cockles can only survive in the salty waters of certain reservoirs. They are not found in freshwater reserves.

Comparison Table Between Clam and Cockle

Parameters of Comparison




Clams are bivalve mollusks commonly found in both freshwater as well as saltwater reserves.

Cockles are bivalve mollusks that naturally grow in the saltwater, briny reserves around the world.


The shell of a clam can be oval, rectangular, or elongated.

Cockles have distinctive heart-shaped shells that are covered with slightly ribbed patterns.

Extend of categorization

Clam is a broader category of classification.

Cockle is a narrower category of classification.

Location in the Sea

Clam can be found closer to the sea shore.

Cockles are commonly found closer to the sea bed.

Raw Consumption

Clams can be consumed in their raw state.

It is imprudent to consume raw cockles. They should be cooked thoroughly or steamed to obtain the best results.


Clams are larger than cockles.

Cockles are much smaller than clams.


All clams are not cockles.

All cockles are clams.

What are Clams?

The variety of shellfish sold in the market is truly boundless. Clams are one of the most well-known and beloved shellfish assortment available at most seafood restaurants globally. These bivalve mollusks occur naturally in the freshwater reserves around the world. The term ‘clams’ functions as a broader category of classification as it generally includes within its folds all the other varieties of bivalve mollusks.

Clams are available in different shapes and sizes. Their bodies are protected by a strong exoskeleton in the form of a shell. A clam’s shell comprises of two equal sections that are joined together. The soft body that remains secured inside the shell does not have a mouth or a head.

However, these mollusks do have an internal renal system, circulatory system, a mouth, and a heart. Clams use siphons to breathe and are commonly found in the sandy or muddy regions of the reservoir. They can be consumed in their raw state, however, they taste best when baked or boiled.

What are Cockles?

Cockles are generally identified as a distant relative of the clam familial order. They are found in the briny waters around the world. The cockle category of bivalve mollusks is much smaller than clams. They are generally located closer to the sea bed.

Cockles also have a strong exoskeleton to protect their soft interiors. The distinctive shell shape and appearance of a cockle sets it apart from the rest of the shellfish variants. The heart-shaped cockle shell features quite distinct ribbed patterns. These patterns can never be replicated by other shellfish variants.

Cockles thrive on the sandy and muddy areas around the briny waters and feed on plankton to grow. These mollusks taste best when cooked thoroughly. Meticulously washing them is important before beginning the cooking process. This eliminates the excessive sand from their shells. They can be fried, steamed, or boiled. However, consuming raw cockles can cause severe health ailments.

Main Differences Between Clam and Cockle

  1. The main difference between a clam and a cockle is that the former bivalve mollusks can be found in both freshwater and saltwater environments, while cockles can only be obtained from saltwater bodies. They are briny mollusks that thrive within a saltwater habitat.
  2. The word clam is used as a broad classificatory term, while cockle is used in a much narrower sense.
  3. The overall shape of each mollusk’s shell is also quite different. Cockles usually have an oval or heart-shaped, slightly ribbed shell. Their shells have distinctive patterns that easily differentiate them from clams. Conversely, clams occur in a variety of shapes and sizes. They can be triangular, oval, or elongated.
  4. Cockles are commonly found closer to the bottom of the sea, while clams are usually found closer to the surface. Clams do not live near the sea floor.
  5. Clams are fit to be consumed raw. However, consuming cockles raw is not very advisable. They taste best when steamed and served with a butter and lemon dressing. Consuming cockles raw may lead to serious health issues.
  6. The size of each of these bivalve mollusks also sets them apart from one another. Cockles are much smaller than clams.
  7. All cockles are clams, as they belong to the clam family. However, all clams may not be cockles as there are other clam variants that occur naturally.


Both clams and cockles are bivalve mollusks that are commonly used in the preparation of some of the most renowned sea-food delicacies. Common people usually find it difficult to differentiate between the two. It does take a trained eye to distinguish between these two bivalve mollusks.

Their dissimilarities become fairly obvious right from the specific appearance of each variant. The shell of a cockle is heart-shaped and has definitive patterns to easily set it apart from the clam category. Alternatively, clams can be of varying shapes and sizes. However, the specific patterns on a cockle’s shell are never replicated by a clam shell.

Each mollusk lives in a different natural habitat. Clams occupy both freshwater and saltwater reservoirs, while cockles can be found only in the saltwater bodies around the world. The size of each mollusk’s shell also makes the difference between them quite telling. Clams are much more sizable than cockles.

Although clams and cockles are used interchangeably in most seafood restaurants for the preparation of several renowned dishes, there are several dissimilarities between these two mollusk variants. For any seafood enthusiast, cognizing these conspicuous differences is important.


  1. https://royalsocietypublishing.org/doi/abs/10.1098/rspb.2018.2684
  2. https://academic.oup.com/zoolinnean/article-abstract/136/3/321/2631244