How many calories in
tuna?
Canned tuna in water is around 132 calories per 100g with 28g of protein — one of the highest protein-to-calorie ratios in any common food. It's a stalwart of cutting diets because a single can lands near 190 calories for almost 30g of protein.
Common serving sizes.
Calories scale with portion. Here's how a typical tuna serving translates in your tracker:
What 132 calories means.
Protein-dense — 21.2 g of protein per 100 kcal makes tuna an efficient choice for hitting a protein target while managing calories.
Skip the lookup. Snap the plate.
Point your iPhone camera at tuna and Spotwell's on-device AI estimates the portion and macros in under a second — no manual entry, no barcode hunting.
Download on theApp StoreQuick answers.
How many calories in tuna?
Tuna has approximately 132 calories per 100g (canned, in water). A typical serving — 1 can (142g, drained) — comes in at 187 calories.
How much protein is in tuna?
28g of protein per 100g (canned, in water). That puts tuna at roughly 21.2g of protein per 100 calories — a useful lens when comparing to other protein sources.
How do I log tuna accurately?
The simplest method: weigh it on a kitchen scale, then enter grams in your tracker. With Spotwell, you can skip the scale — point the camera at the plate and the AI estimates the portion in under a second. Adjust the value if it looks off.
Is tuna good for weight loss?
It depends on your overall calorie target. Tuna sits in a moderate calorie range. It can fit any goal — weight loss, maintenance, or muscle gain — when portioned to your daily target.