Keto seafood: compare fish, shellfish, and preparation

Direct answer: seafood does not have a single keto classification. Many plainly prepared fish records have very little calculated net carbohydrate, while shellfish, sauces, breading, pickling, and composite dishes can change the comparison. The relevant question is which seafood record, prepared how, and in what portion.

Medical disclaimer. This article is for general educational purposes only and is not medical advice. It is not a substitute for professional diagnosis or treatment. Always consult a qualified healthcare provider before starting the ketogenic diet or making changes to your diet, exercise, or medication — especially if you are pregnant or breastfeeding, take medication, or have a medical condition such as diabetes, or kidney, liver, or heart disease. See our editorial & medical-review policy.

A fish dish is more than the fish

The database keeps cooked, canned, smoked, pickled, coated, and composite foods separate. This is important because the cooking or preservation description can carry ingredients that a generic “fish” value misses. Use the linked entry’s source wording rather than applying one record to another preparation.

Browse seafood by preparation

↔Small-screen view: this comparison table scrolls sideways. Swipe or drag it horizontally to see every column.

Food decision	Records to compare	What to check next
Plain fish and canned fish	Fish, cod, grilled, fish, tuna, canned, fish, salmon, canned	Whether the current product includes oil, sauce, seasoning, or a different drained weight.
Shellfish and mollusks	Crab, clams, baked or broiled, oysters, canned	Exact species, preparation, sauce, and the portion you plan to serve.
Smoked, pickled, or preserved fish	Fish, salmon, smoked, fish, sardines, canned, fish, pickled	Ingredients, sodium, sugar, oil, and package portion.
Seafood dishes with added ingredients	Shrimp cocktail, fish, stick, cocktail sauce	Whether breading, batter, sauce, or a restaurant recipe is part of the food being counted.

Read the comparison in context

Every entry reports USDA nutrients per 100 g and calculates one listed household portion from the source’s gram weight. This makes records comparable, but it does not tell you a preferred serving size or predict an individual ketone response. On individual pages, calculated net carbs are total carbohydrate minus dietary fiber, capped at zero.

The data are not a seafood-safety, allergen, mercury, sustainability, pregnancy, or medication guide. Those questions require the current product information and, when relevant, advice from an appropriate clinician or official public-health source. For food-composition decisions, use the exact record; for practical shopping and storage, see the keto grocery-shopping guide and freezing and storage guide.

Continue the meal comparison

Compare the supporting components separately: vegetables, dairy & alternatives, and fats & condiments. The keto food list offers a broader planning framework without replacing individual labels or food records.

Complete seafood record directory

Browse all 60 selected USDA records in this seafood group

Entries are grouped by food concept, then by the exact USDA food form. Open the record that matches the preparation and product you are comparing.

Abalone

• Abalonewhole food

Anchovy

• Anchovywhole food

Bass

• Bass, baked or broiledbaked · broiled
• Bass, grilledgrilled
• Bass, steamedsteamed

Calamari

• Calamari, cookedcooked

Catfish

• Catfish, grilledgrilled
• Catfish, steamedsteamed

Caviar

• Caviarwhole food

Clams

• Clams, rawraw
• Clams, baked or broiledbaked · broiled
• Clams, cannedcanned
• Clams, steamed or boiledboiled · steamed

Cod

• Cod, grilledgrilled
• Cod, steamedsteamed

Crab

• Crabwhole food
• Crab, cannedcanned

Crayfish

• Crayfish, cookedcooked

Escargot

• Escargotwhole food

Fish

• Fish, rawraw
• Cannedcanned
• Pickledpickled
• Smokedsmoked
• Stickstick

Flounder

• Flounder, grilledgrilled
• Flounder, steamedsteamed

Haddock

• Haddock, grilledgrilled
• Haddock, steamedsteamed

Imitation crab meat

• Imitation crab meatimitation

Lobster

• Lobsterwhole food

Mackerel

• Mackerel, grilledgrilled
• Mackerel, cannedcanned

Mussels

• Musselswhole food

Oysters

• Oysters, rawraw
• Oysters, cannedcanned
• Oysters, steamedsteamed

Perch

• Perch, grilledgrilled
• Perch, steamedsteamed

Pompano

• Pompano, grilledgrilled
• Pompano, steamedsteamed

Salmon

• Salmon, rawraw
• Salmon, cannedcanned
• Salmon, smokedsmoked
• Salmon, steamedsteamed

Sardines

• Sardines, cannedcanned

Scallops

• Scallops, grilledgrilled
• Scallops, steamed or boiledboiled · steamed

Shrimp

• Shrimp, baked or broiledbaked · broiled
• Shrimp, cannedcanned
• Shrimp, drieddried
• Shrimp, grilledgrilled
• Shrimp, steamed or boiledboiled · steamed

Shrimp cocktail

• Shrimp cocktailwhole food

Tilapia

• Tilapia, steamedsteamed

Trout

• Trout, steamedsteamed

Tuna

• Tuna, rawraw
• Tuna, cannedcanned
• Tuna, cookedcooked

Turtle

• Turtlewhole food

Whiting

• Whiting, steamedsteamed

Source and method

This hub organizes selected seafood entries from USDA FoodData Central’s Survey (FNDDS) release. Each food page gives the FoodData Central ID, source food description, preparation state, selected portion, and source traceability. A restaurant dish, fish-counter item, or package is only comparable when its form and ingredients match the record.

1. U.S. Department of Agriculture, Agricultural Research Service. FoodData Central Survey (FNDDS) 2021–2023, released October 31, 2024. FoodData Central documentation, dataset downloads

Article history

1. August 24, 2026First published