1. Check the restaurant’s own information
Look on the menu, website or app for the exact item and size you ordered. Check the country too: a chain’s recipe and serving can vary between markets. The calorie figure may describe one slice, a whole pizza or a meal without a drink.
Ask whether dressing and sides are included. A restaurant’s published figure describes its specified serving; your changes can alter the total. Nutrition information is not available at every restaurant.
Sources: FDA: calories on the menu
2. Separate the meal into parts
The following numbers are hypothetical arithmetic examples, not restaurant nutrition data or typical portion values. They show how to use information you find. Replace them with the figures for your own order.
| Order | Example information | Total to record |
|---|---|---|
| Half a pizza | Whole pizza 1,200 calories; you eat 4 of 8 equal slices | 600 kcal |
| Burger meal | Burger 500 + fries 300 + drink 150 + dip 100 | 1 050 kcal |
| Salad with dressing | Salad 350 + separately listed dressing 120 + bread 80 | 550 kcal |
3. When nutrition information is unavailable
Choose the closest matching dish in the calculator. Pizza toppings and crust, burger size and the main salad ingredients matter more than a name alone. Estimate the amount and any separate sauces. If you use a complete dish entry, do not count dressing it already includes a second time.
For example, an assumed portion of 300–450 g at 180 calories per 100 g gives 540–810 calories. This compares two portion assumptions; it is not a universal error range for restaurant food. The 180-calorie value may also be wrong if the recipe differs.
4. Record the estimate and continue your day
You can name the entry “Restaurant lunch, estimate” and add the best supported calorie figure. The name reminds you of its uncertainty later. One uncertain meal does not call for punishing yourself or skipping your next meal.
A photo can help you remember a meal, but hidden oil, butter or dressing cannot be reliably measured from it. Calotank’s photo estimate is a paid Premium feature and remains an estimate. Manual logging is free.
Sources and content
Sources checked on 5 October 2026. Text and recipe calculations: Calotank. Images are AI-generated illustrations. Recipes are not presented as test-kitchen measurements. General information, not individual nutrition advice. Creator and corrections.