The barcode scan is our accuracy anchor

Photo-based estimation is genuinely useful for homemade meals, but it's the wrong tool for a box of cereal or a protein bar — those already come with exact nutrition facts printed on the package, and estimating them from a photo would just introduce error where none needs to exist.

That's why Calorie treats barcode scanning as a separate, higher-precision path. Point the camera at a barcode, and the app pulls the manufacturer's actual nutrition label instead of guessing, so packaged food logs at the same accuracy as reading the label yourself, just faster.

In practice, most people end up using both modes in the same day: a barcode scan for the yogurt and the granola bar, a photo for the dinner they cooked. Together they cover the two most common ways food actually shows up in a day, without forcing either one into the wrong workflow.