How to count calories: a practical method for real life

How many calories should you aim for?

Counting only helps if you know what you're counting toward. Start with an estimate of your daily needs: resting energy from the Mifflin–St Jeor equation, multiplied by how active you are, then adjusted for your goal and pace. Our calorie calculator does the maths in your browser, and the guide to how many calories you should eat a day walks through every step with a worked example.

Without a target, a day's total is just a number; with one, it tells you whether today ran high, low or about right. Treat that number as a first guess, not a verdict. After two or three weeks of honest logging, your weight trend tells you whether it fits, and you adjust from there.

When should you log what you eat?

As you eat, or just before. Memory is unreliable with food: the handful of nuts, the second glass of juice, the spoon of honey in your tea all fade by the evening. Logging plate by plate takes a moment each time and keeps the day honest without much effort.

A few habits make it stick:

• Log before the first bite. The plate is complete and the photo is easy.
• Don't forget drinks. Juice, soda, milky coffee and sweetened tea all count.
• Snacks are meals too. Small, frequent bites add up quietly.
• Keep the whole day in one place. Meals split across notes, photos and memory are how things go missing.
• Use reminders if they help. A gentle nudge at your usual mealtimes beats trying to rebuild the whole day at midnight.

How do you count calories without a scale?

You don't need to weigh everything. Three tools cover most days:

• Your hand. A palm-sized piece of meat or fish, a fist of rice or pasta, a cupped hand of nuts, a thumb of butter. Your hand goes everywhere you eat.
• Your plate. Half vegetables, a quarter protein and a quarter starch is an easy picture to estimate from, and to photograph.
• Everyday units. One egg, one banana, one tablespoon, one bowl. Learn a few and you can estimate most meals.

Weigh a usual portion once in a while to keep your eye honest. And when a photo is easier than all of this, an AI calorie counter writes the first draft for you.

How do you read calories on a food label?

Most labels give values per 100 g (or per 100 ml for drinks), and often per serving too. The per-100 g column is the one to trust, because “a serving” is whatever the maker decided it is. The sum is simple:

kcal eaten = kcal per 100 g × grams eaten ÷ 100

Say your oats are 379 kcal per 100 g, like the rolled oats in our chart, and you pour 40 g: 379 × 40 ÷ 100 ≈ 152 kcal. Do the same for protein, carbs and fat if you track macros. For loose foods with no label, a calorie chart gives you the same per-100 g values. Try ours here:

Scanning the barcode skips the arithmetic: the app finds the product and does the sum for your grams. More in our barcode guide.

How do you count calories in homemade food?

Home cooking has no label, so you make one. The recipe method works for any dish:

1. Write down every ingredient with its weight, including the oil.
2. Add up the calories of all the ingredients.
3. Weigh the finished dish (weigh the empty pot first, or serve into a bowl you know).
4. Divide: your share of the weight is your share of the calories.

Here's a shepherd's salad for two, with values from our chart:

Half the bowl is about 187 kcal, and about two-thirds of the total comes from the oil. The bowl works out at about 57 kcal per 100 g, close to the 55 our chart lists for a shepherd's salad. Do this once for a dish you cook often, save it as your own food, and next time it's one tap.

How do you count calories when eating out?

• Find the closest match. A doner wrap, a lahmacun, a slice of pizza: most restaurant food has a close cousin in a calorie chart, like chicken doner at 180 kcal per 100 g.
• Use published values when they exist. Some chains list calories on the menu or their website; when they do, start there.
• Photograph the plate. Mixed restaurant plates are exactly what photo estimates are for.
• Count the extras. Bread from the basket, butter on top, sauces, the drink and the shared dessert.
• Allow for a little more fat. Restaurant kitchens can use more oil or butter than you would at home, so when you're unsure, pick the richer option.
• Log it and move on. A rough entry keeps your week readable. Skipping the log because the meal was big only leaves a gap.

Eating out in Turkey? Our post on counting calories when eating out in Turkey has more tips.

What matters most when you count calories?

Think of it as an 80/20 rule of thumb, not a measured ratio: a handful of things carry most of the uncertainty, so get those roughly right and relax about the rest. If you only have energy for one thing, make it the oil.

• Oils, butter and dressings. The most energy-dense things in the kitchen, and the easiest to miss.
• Drinks. Juice, soda, milky coffee, sweetened tea and alcohol.
• Bread, pastries and sweets. Easy to add without noticing.
• Nuts and nut butters. Walnuts are 654 kcal per 100 g, so small handfuls carry big numbers.
• Portions of rice, pasta and other starches. A heaped plate and a modest one can be twice apart.

Meanwhile, cucumber is 15 kcal per 100 g, and weighing it to the gram changes nothing. What changes everything is consistency: logging most days, roughly right, for weeks. That's what turns numbers into a pattern you can use, and it's why a food diary you keep beats a perfect one you abandon.

Questions people ask