Grapefruit runs 42 calories per 100g. Light enough that a generous portion barely moves the needle.
Calories scale with portion. Here's how a typical grapefruit serving translates in your tracker:
Point your iPhone camera at grapefruit and SpotWell's on-device AI estimates the portion and macros in under a second — no manual entry, no barcode hunting.
Download on theApp StoreGrapefruit has approximately 42 calories per 100g. A typical serving — 3 oz (85g) — comes in at 36 calories.
0.8g of protein per 100g. That puts grapefruit at roughly 1.9g of protein per 100 calories — a useful lens when comparing to other fruits sources.
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.
It depends on your overall calorie target. Grapefruit is naturally low-calorie at 42 kcal per 100g, so it's easy to fit into a deficit.