How many calories are in canned tuna?
Canned tuna has 99 calories per 3 oz drained (85 g) — that's 116 calories per 100 g, roughly 5% of a 2,000-calorie day. Most of those calories come from protein.
USDA FoodData Central · light, canned in water, drained · FDC 171986
Calories by portion
| Portion | Calories | Protein | Carbs | Fat |
|---|---|---|---|---|
| 3 oz drained (85 g) | 99 | 21.7 g | 0 g | 0.7 g |
| 100 g | 116 | 25.5 g | 0 g | 0.8 g |
| 1 oz (28 g) | 33 | 7.2 g | 0 g | 0.2 g |
Where the calories come from
Protein 93% Carbs 0% Fat 7%
Calories computed from USDA per-100 g data (FDC 171986, SR Legacy). light, canned in water, drained. The macro split uses general Atwater factors (protein and carbs ≈ 4 cal/g, fat ≈ 9 cal/g) and is approximate.
Canned tuna is one of the lowest-calorie ways to put real protein on a plate. A standard 3 oz drained serving (85 g) carries only about 99 calories, and 100 g comes in at 116 calories — figures that are remarkably low for something delivering roughly 22 g of protein in that same serving. Where most foods make you weigh calories against what you get, tuna gives you a near-pure dose of protein for almost nothing in calories. The reason sits in the macro split, and it’s an unusually clean one.
Where the calories come from
Almost all of them are protein. Light tuna canned in water runs under 1 g of fat per 100 g and has zero carbohydrate, so there’s nothing left to drive the calorie count except the protein — and protein costs 4 calories a gram versus 9 for fat. Run a 3 oz serving through that math and the ~22 g of protein essentially is the ~99 calories; the trace of fat barely registers. That’s the opposite of a calorie-dense food like a nut or an oil, where fat does most of the work. Tuna is protein-dense without being calorie-dense, which is a rare and useful combination on any plan where calories are counted.
The packing medium is the one variable
The one thing that moves the number is how the tuna is packed. The figures above describe light tuna canned in water, drained — the lean default. Switch to tuna in oil and the calories climb, because the fish soaks up fat from the packing oil and even a thorough draining leaves some behind; a can in oil can run well above its water-packed equivalent. So if calories are the priority, water-packed and well-drained is the choice, with oil reserved for when you specifically want the extra richness. Salt and brand don’t change calories meaningfully — that’s a sodium question, not a calorie one. Compared with chicken breast at about 140 calories per 3 oz cooked, tuna lands even lower per gram of protein, with no cooking required and a multi-year shelf life.
For the full protein story — how a single can covers a meaningful slice of a daily target — see protein in canned tuna.
Packaged canned tuna options, graded
Prefer something off the shelf? Here are the best-graded canned tuna in our catalog — each scored on our transparent Labelgrade. Check the calorie line on each label for your goal.
-
Labelgrade 83/100 · 110 cal · 24 g protein
Check price on Amazon -
Labelgrade 80/100 · 50 cal · 11 g protein
Check price on Amazon -
Labelgrade 79/100 · 60 cal · 13 g protein
Check price on Amazon
Buy links are affiliate links — we may earn a commission at no extra cost to you. The Labelgrade is independent of any affiliate relationship. More.
Frequently Asked Questions
How many calories are in a 3 oz serving of canned tuna?
About 99 calories in a 3 oz drained serving (85 g), based on 116 calories per 100 g (USDA FDC 171986). Almost all of that is protein — roughly 22 g — which makes tuna one of the most calorie-efficient proteins you can buy.
How many calories are in a can of tuna?
A standard 5 oz (142 g) can drains down to roughly 4 oz of fish, which lands around 130 calories. The exact number depends on solid- versus chunk-pack and whether it's in water or oil, but a whole drained can of light tuna in water is well under 150 calories for about 30 g of protein (USDA FDC 171986).
Why is canned tuna so low in calories?
Because it's almost pure protein with very little fat. Light tuna canned in water carries under 1 g of fat per 100 g, and protein has 4 calories a gram versus 9 for fat. With no carbohydrate either, there's nothing in tuna to drive calories up except the protein itself — which is exactly why it's a staple on calorie-controlled plans.
Does tuna in oil have more calories than tuna in water?
Yes, noticeably more. Tuna packed in water stays near 116 calories per 100 g. Tuna in oil soaks up fat from the packing medium and runs higher even after draining, since some oil clings to the fish. For the lowest-calorie option, choose water-packed and drain it well.
How does canned tuna compare to chicken breast on calories?
They're close, and both are excellent. A 3 oz serving of drained tuna is about 99 calories; 3 oz of cooked chicken breast is roughly 140. Tuna edges it out per gram of protein because it carries almost no fat, while it needs no cooking and keeps for years on the shelf.
When was this data last verified?
2026-06-18, against USDA FoodData Central FDC 171986 (Fish, tuna, light, canned in water, drained; SR Legacy). We re-verify reference pages periodically and update when USDA revises the entry.
Whole-food values are USDA reference data, not a Labelgrade (that score is for branded packaged products). See our methodology and the TDEE calculator to turn this into a daily target.