How many calories are in 100g of tuna?

For canned light tuna packed in water, drained, 100g is typically about 116 calories. That makes it one of the lowest-calorie protein options in the seafood aisle.

Fresh tuna varies by species and cut. Many raw tuna steaks fall roughly in the 100 to 150 calorie range per 100g, depending on fat content. Higher-fat species such as bluefin can be higher than leaner varieties like skipjack or light tuna.

Oil-packed tuna is the biggest calorie jump. Because oil adds fat, 100g can land much closer to 180 to 250 calories or more, depending on how much oil remains after draining.

What 100g of tuna gives you besides calories

Tuna is known for being protein-dense. In many tuna products, 100g provides around 20 to 25g of protein, which is why it’s popular for meal prep, post-workout meals, and high-protein diets.

It is also naturally low in carbohydrates. If you’re tracking macros, tuna usually contributes nearly all of its calories from protein and, depending on the product, fat.

Tuna also provides nutrients such as selenium, vitamin B12, niacin, and, in many varieties, omega-3 fats. The exact nutrient profile changes based on species and whether the tuna is fresh, canned in water, or canned in oil.

Why the calorie count changes so much

The biggest factor is packing medium. Tuna in water is much leaner than tuna in oil because water doesn’t add calories, while oil does.

Another factor is whether you’re weighing tuna before or after draining. Drained canned tuna is the most common way calorie counts are listed, but undrained tuna can look significantly more calorie-dense on paper.

Species matters too. Light tuna, albacore, yellowfin, and bluefin do not all have the same fat content, so a 100g serving is not identical across all tuna products.

How to track tuna calories accurately

For the most accurate log, match the exact form you ate: raw, cooked, canned in water, canned in oil, drained, or undrained. If you’re using canned tuna, weigh the drained solids when possible.

Read the nutrition label carefully because brands can differ. A label may list calories for a serving size that is not exactly 100g, so converting helps avoid errors.

If you’re using tuna as part of a workout meal plan, tracking the full meal matters too. Add the calories from mayo, oil, crackers, rice, pasta, or bread, since tuna itself is often only one part of the total.

Tips

• Choose tuna in water if you want the lowest calories per 100g.
• Drain canned tuna before weighing it for the most accurate calorie count.
• Watch out for mayo, oil, and sauces, which can double the calories in a tuna meal.
• Use fresh tuna steak or canned tuna interchangeably only if you compare the exact product and preparation.
• If you train at home, Fitnit can help track reps and form so you can pair your nutrition logging with a consistent routine.