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 AI estimates the portion and macros in a few seconds. Check it, adjust anything that looks off, and log it.
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 a few seconds. 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.