Seafood Calorie Calculator

Calculate Calories in Fish & Seafood

Seafood Calorie Lookup

Search from 235+ seafood items · All values per 100g

Today's Seafood Intake

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Seafood Calorie Calculator: Check Calories, Protein & Omega-3 in 235+ Fish and Shellfish

Most white fish contain between 70 and 110 calories per 100g raw, while oily fish like salmon and mackerel range from 180 to 210 calories per 100g, and the cooking method can change those figures by 30% or more. Our free seafood calorie calculator gives you exact values for over 235 fish and shellfish varieties, covering calories, protein, fat, omega-3, mercury levels, allergens and UK seasonality, all per 100g or any portion size you choose.

We built this tool using the same product data we work with every day as a London wholesale fishmonger supplying restaurants, hotels, and caterers across Greater London. Every species in the database is one we handle, fillet and deliver, so the figures reflect the actual fish on your plate, not generic averages.

Whether you're tracking macros, planning a heart-healthy diet around omega-3, or a chef costing out menu nutrition, the calculator below gives you the answer in seconds.

What the Seafood Calorie Calculator Tells You

For every fish or shellfish you look up, the calculator returns a full nutrition and sourcing profile:

  • Calories (kcal): Per 100g by default, or for any custom amount in grams, ounces, fillets, or portions.
  • Macronutrients: Protein, carbohydrates, fat, fiber, and sugar, with the calorie contribution of each.
  • % Daily Value: Every figure is benchmarked against a standard 2,000 kcal/day reference intake.
  • Omega-3 (EPA + DHA): Measured against the 0.5g daily target referenced in NHS and WHO guidance, with a progress bar showing how far one portion takes you.
  • Mercury level: Low, moderate, or high, with portion-frequency guidance for moderate and high-mercury species.
  • Allergen flags: Fish, crustacean, and mollusc allergens declared in line with UK food information regulations.
  • Sustainability status: Wild-caught vs farmed, and responsible sourcing indicators.
  • UK season: When each species is in season in British waters, so you can buy at peak quality and best value.

You can also switch between raw and cooked values, grilled, baked, fried, poached, and steamed, because a battered, deep-fried cod portion is a very different number from the same fillet poached.

How to Use the Calculator

  1. Search or filter: Type a seafood name into the search bar, or use the quick filters: Top Omega-3, Lowest Calorie, High Protein, Low Mercury, or Sustainable to browse by goal.
  2. Set your portion: Enter the amount and choose your unit (grams by default; all base values are per 100g).
  3. Choose the cooking method: Raw, grilled, baked, fried, poached, or steamed; calories and fat adjust automatically.
  4. Hit Calculate: You'll get the full breakdown: calories, macros, % Daily Value, omega-3 vs your daily target, mercury rating, allergens and UK season.
  5. Track or compare: Add the result to the Meal Tracker to total your seafood intake for the day, or send two results to the Compare tab for a side-by-side nutrient table.

Omega-3: Why the Calculator Tracks EPA + DHA

Not all omega-3 claims are equal. The forms that matter most for heart and brain health are EPA and DHA, which are found almost exclusively in seafood. The plant form (ALA, found in flaxseed and walnuts) converts to EPA/DHA poorly.

Our calculator measures combined EPA + DHA per portion against a 0.5g daily reference target, in line with the widely used NHS/WHO benchmark. One 100g portion of halibut hits 100% of that target; one portion of mackerel covers several days' worth. This is why the Top Omega-3 filter is the most-used filter on the tool; it surfaces the species that do the heavy lifting.

Mercury Levels and Safe Portions

Larger, longer-lived predatory fish accumulate more mercury than smaller, shorter-lived species. The calculator flags every species as low, moderate, or high mercury:

  • Low mercury (cod, haddock, salmon, prawns, mussels): no portion restrictions for the general population.
  • Moderate mercury (halibut, sea bass, tuna): UK guidance suggests limiting to around two portions per week, particularly for pregnant women.
  • High mercury (swordfish, shark, marlin): the FSA advises pregnant women to avoid these entirely, and others limit to one portion per week.

If mercury is a priority, for example, during pregnancy, use the Low Mercury filter to browse only unrestricted species.

Does Cooking Method Change Seafood Calories?

Yes, significantly. The fish itself barely changes, but what you add does:

  • Poaching, steaming and grilling add little or nothing. A grilled cod fillet stays close to its raw 78 kcal/100g.
  • Baking with oil or butter typically adds 20–40 kcal per 100g, depending on how much fat is used.
  • Pan-frying adds roughly 50 kcal per 100g from absorbed oil.
  • Battering and deep-frying are the big ones. Battered, fried cod can exceed 200 kcal per 100g, more than double the raw value, with most of the extra coming from the batter absorbing oil.

The calculator's cooking-method selector applies these adjustments automatically, so you're tracking what you actually eat, not the raw fillet weight.

Buy the Fish You Just Calculated

Every species in this calculator is fish we cut and deliver across Greater London daily, with orders accepted up to 11:59 PM for next-day delivery. Browse our fresh fish range, shellfish collection, or for restaurants, hotels, and caterers, our wholesale seafood service.

🛡️ *Disclaimer: This calculator is provided for general nutritional information and is not a substitute for professional dietary or medical advice. If you have specific health conditions, allergies, or are pregnant, consult a qualified healthcare professional. Allergen information: all listed products contain fish, crustaceans, or molluscs, as flagged per item.

*Nutrition data last reviewed: June 2026.

Sources

  1. McCance & Widdowson's Composition of Foods Integrated Dataset (CoFID), Public Health England — UK reference values for energy, protein, fat and carbohydrate per 100g. Accessed June 2026.
  2. NHS — Fish and shellfish — weekly portion recommendations, oily vs white fish guidance, and mercury advice. Accessed June 2026.
  3. NHS — Foods to avoid in pregnancy — guidance on shark, swordfish, marlin and tuna limits during pregnancy. Accessed June 2026.
  4. Food Standards Agency — Food allergy and intolerance — fish, crustacean and mollusc allergen declaration requirements under UK food information regulations. Accessed June 2026.
  5. EFSA — Dietary Reference Values for fats, including EPA and DHA — basis for the daily omega-3 (EPA + DHA) intake target used in this calculator. Accessed June 2026.
  6. Marine Stewardship Council (MSC) — sustainable and responsibly sourced seafood certification standards. Accessed June 2026.