Do calories change when food is cooked?

Barely. Cooking moves water in or out, so the weight changes a lot while the calories stay close to the same. That is why 100 g of cooked rice has about a third of the calories of 100 g of dry rice. The exceptions are fat that melts out and gets poured away, and oil the food soaks up, which adds calories.

Should I weigh food raw or cooked?

Either works, as long as the number you look up matches the state you weighed. Raw is more consistent for meat, rice and pasta, because cooked weight depends on how long it cooked. For a whole recipe, weigh ingredients raw, and weigh the finished dish once it is cooked.

How do I count calories in a recipe without a food scale?

Use the package labels for the totals (a 500 g bag of pasta, a 400 g can), count oil by the spoon, then split the dish into equal portions and divide. It is less precise than weighing, but for a dish you make often, a consistent estimate is more useful than an exact number you never record.

Do I count all the oil I cooked with?

For sautéing, roasting and stir-frying, yes, count all of it. Most of it ends up on the food, and a tablespoon of olive oil is about 120 calories. If a lot of oil is visibly left in the pan, count the oil that went into the food and leave out what you poured away.

How do I count calories in homemade soup or chili?

The same way as any recipe. Add up the ingredients, weigh the pot when it is done (subtract the weight of the empty pot), and divide. Soup is mostly water, so calories per gram are low and a ladle weighs more than it looks. Weighing the bowl you actually serve is more reliable than counting ladles.

How to Count Calories in Homemade Food and Recipes

By Samipan Bandyopadhyay, developer of Fitto AI

Cooking at home is where food logs tend to go vague. A packaged snack has a label and a restaurant chain publishes a menu, but the curry you made on Sunday has neither. So it gets logged as “chicken curry, 1 bowl” from whichever database entry looked closest, and that entry was someone else’s recipe with someone else’s oil.

There is a better way, and it takes about two minutes per recipe once you have done it once.

The cooked-weight method, step by step

This is the standard way to get calories per portion for anything you cook in a batch: soup, chili, stew, curry, casseroles, pasta bakes, overnight oats.

Weigh your empty pot or dish and write the number down, so you can subtract it later.
Add up the calories of every ingredient as it went in. Use the label on the package where there is one, and a reference such as USDA FoodData Central for fresh food. Count the oil, butter and anything else that went into the pan.
Weigh the finished dish in the pot and subtract the weight of the empty pot. That is the cooked weight.
Divide total calories by cooked weight to get calories per gram.
Weigh your portion and multiply. Write calories per gram on the container lid, and every later portion is one multiplication.

Step 3 is the one people skip, and it is the one that makes the method work. Simmering drives water off and rice or pasta soaks water up, so the weight of the dish moves a lot while its calories stay the same. Weighing the result catches that change, whatever it was.

A worked example: one pot of chicken and rice

Here is the arithmetic for a simple one-pot dish, using reference values from USDA FoodData Central.

Ingredient (as it went in)	Amount	Calories per 100 g	Calories
Chicken breast, raw	600 g	120	720
White rice, long-grain, dry	300 g	365	1,095
Olive oil	2 tbsp (27 g)	884	239
Water and dried spices	–	–	close to 0
Total			2,054

Say the finished dish weighs 1,600 g once the empty pot’s weight is taken off. Then:

2,054 kcal ÷ 1,600 g = 1.284 kcal per gram
A 400 g bowl is 400 × 1.284 = about 514 kcal

The cooked weight in your kitchen will be different. That is the point: it depends on your pot, your heat and how long you cooked it, and it is why weighing the finished dish matters.

A common mistake: mixing up raw and cooked numbers

One of the easiest ways to get a home-cooked meal wrong is to weigh food in one state and look it up in the other. Water changes the weight, so the calories per 100 g change a lot between raw and cooked:

Food (USDA FoodData Central)	Calories per 100 g, raw or dry	Calories per 100 g, cooked
White rice, long-grain	365 (dry)	130 (boiled)
Pasta	371 (dry)	158 (boiled)
Chicken breast, skinless	120 (raw)	165 (roasted)

Weigh 300 g of cooked rice and look it up as dry rice, and you log 1,095 kcal instead of 390, nearly three times too much. Go the other way with chicken, weighing it raw and logging it as roasted, and you overcount by more than a third.

Rice and pasta gain water as they cook, so cooked portions have fewer calories per gram. Meat loses water, so cooked meat has more. Neither is “right”. Pick one, raw or cooked, and use the matching entry every time.

Don’t lose the oil

Fat carries 884 calories per 100 g, more than twice as much as rice or pasta per gram, and a tablespoon of olive oil (about 13.5 g) comes to roughly 120 kcal. In the example above, two tablespoons are more than a tenth of the whole pot.

Oil is also the ingredient a database entry is most likely to get wrong, because every cook uses a different amount. Measure it with a spoon as it goes in rather than pouring from the bottle, and count all of it for sautéing, roasting and stir-frying.

The one honest deduction is fat you can see and pour away: a pool of oil left in the pan, or fat drained off browned mince. Calories do not escape as steam, so steer clear of advice to knock a flat 10% off a recipe “for cooking losses”. The water leaves; the calories stay.

The same applies to photo estimates. A camera can’t see oil that has soaked into food, which is one of the main reasons AI photo counts come in low on home-cooked and restaurant dishes.

Meal prep: do the math once

If you cook a batch on Sunday and eat it all week, the cooked-weight method gets much easier:

Split the batch into equal containers by weight, not by eye. Five containers of 320 g from a 1,600 g pot each carry exactly a fifth of the calories.
Write the calories on the lid. Then logging a container is typing one number.
Save the totals for recipes you repeat. Your usual chili with the same ingredients comes out close to the same every time, so the first calculation keeps working.

When you can’t weigh anything

A family dinner, a dish someone else cooked, a pot you were never going to weigh: you can still log it well.

Estimate your share of the whole. “I had about a quarter of the lasagne” is often easier to judge than grams. If you know roughly what went in, divide.
Use the package sizes. A recipe that used one 500 g bag of pasta and one 400 g can of tomatoes has known totals, even if nothing was weighed.
Photograph the plate. A photo-based estimate is a reasonable first draft, and you can estimate portions with your hands to check it.

A slightly rough number logged every day tells you more than an exact one that only exists on the days you had time to weigh.

How to log homemade food in Fitto AI

Fitto AI doesn’t have a recipe builder. For home-cooked food, there are two routes:

If you worked out the number: describe the meal (“400 g homemade chicken and rice”) or photograph the bowl, then edit the line before you log it. Calories, portion, protein, carbs and fat can all be changed, and nothing is saved until you confirm, so your own calculation is what ends up in the log.
If you didn’t: photograph the plate, or say or type what is in it, and Fitto lists each food it can identify with an estimated portion and calories. For a home-cooked dish, check the portions and add the oil or butter it can’t see.

For packaged ingredients you eat on their own, such as yogurt or a protein bar, barcode scans read the label and are always free.

Sources

U.S. Department of Agriculture, Agricultural Research Service. FoodData Central, SR Legacy: olive oil, salad or cooking (FDC ID 171413); rice, white, long-grain, raw (168877) and cooked (168878); pasta, dry (169736) and cooked (169737); chicken breast, skinless, raw (171077) and roasted (171477). Values per 100 g, retrieved October 2026.