Calorie apps guide
Are calorie counting apps accurate?
Updated October 11, 2026 · MyPlate
An app is as accurate as the food it selected and the portion it assumed. A label or a USDA FoodData Central record for the food you weighed is a checkable number. A photo estimate is not a scale. When two apps disagree, compare both with the portion you can measure.
People ask this before they trust a streak of logged days. The honest answer is conditional. Packaged food with a barcode that matches the package is limited by the label, which is the right source for that product. A homemade stew, a restaurant bowl, or a photo of a mixed plate is limited by whoever guessed the grams of oil, rice, and sauce. No app removes that limit. The job of the app is to store the choice you made so you can compare days.
Three ways a number gets into an app
| Method | What it is good at | Where it slips |
|---|---|---|
| Label or barcode | That package, that serving | You ate more than one serving and logged one |
| USDA-style database search | A named food and a named amount | Cooked versus raw, or a different variety |
| Photo estimate | Speed, so the day gets logged | Hidden oil, stacked food, and portions the camera cannot weigh |
Our food chart is the third column's check, not a photo model. Each row names the FDC ID. A medium raw banana there is 118 g and 105 kcal (FDC 173944). If an app says 90 or 120, it may be using a different size. Our chart does not call 120 a large banana, because the portion we fetched for the medium fruit is 118 g. Weigh yours if the size is different.
A small audit you can do once
Pick three foods you eat every week. Weigh them. Look up the same description in FoodData Central or on the chart. Examples you can copy:
- One large raw egg, 50 g: 72 kcal, 6.3 g protein, 0.4 g carbohydrate, 4.8 g fat (FDC 171287). A large hard-boiled egg is a different record: 78 kcal and 5.3 g fat (FDC 173424).
- 100 g roasted skinless chicken breast: 165 kcal and 31.0 g protein (FDC 171477).
- Two tablespoons of smooth peanut butter, 32 g: 191 kcal (FDC 172470).
If the app matches those rows when you enter the same amount, the database path is fine for those foods. If a photo of the same plate is off by the oil you cannot see, that is the method, not a reason to throw out the egg entry. Read how photo calorie tracking works for the workflow, and keep the label for packages.
Common mistakes
- Treating a user-submitted "homemade lasagna" entry as if it were your lasagna.
- Logging a raw egg's 72 kcal for a hard-boiled egg, or the reverse. Both are in the chart, and they are not the same.
- Expecting a photo to know the tablespoon of olive oil (119 kcal, FDC 171413) poured in the pan.
- Quoting an accuracy percentage the app's own page does not publish. This site does not invent one.
Sources
- USDA FoodData Central IDs on this page, retrieved 11 October 2026.
Set the target with the calorie calculator, log with a method you can audit, and read how to count calories. The MyPlate app is free to download, try every feature free, with a 3-day free trial.
Frequently asked questions
Are calorie counting apps accurate?
They are accurate when the food record matches what you ate and the portion is right. They are not accurate when the database food is a different recipe or the portion is a guess.
Is a barcode better than a photo?
For a packaged food, the label is the manufacturer's declaration for that serving. A barcode that opens that label is the better path. A photo is an estimate of a portion the camera cannot weigh.
Is USDA FoodData Central the same as an app database?
FoodData Central is a USDA database of specific foods. Apps may use it, a commercial set, or user-entered foods. Always check that the name matches, down to cooked versus raw.
Why do two apps disagree?
They picked different foods or different portions. A cup of cooked oatmeal in our chart is 166 kcal (FDC 173905). Another entry might be dry oats or a larger cup.
How should I check an estimate?
Weigh the food once and compare the app with the FDC row or the label. If they disagree, keep the weighed source.
Does that mean tracking is pointless?
No. A consistent method shows trends. It does not become a laboratory analysis. Use it next to your TDEE, and correct the foods that are systematically off.