Calories to Maintain Weight, Lose Weight or Gain Weight

Counting your calories to maintain weight is something most people never dream of doing. Normally when people get concerned about calories is when they want to know the calories needed to lose weight and in some cases to gain weight. The real reason people need to know their calories to maintain weight is so that they can adjust it to lose or gain.

I hope I can demystify some of the confusion and leave you with some solid advice you can use to either adjust your diet or pick up a healthy program somewhere else. So let's start with the basics and move on from there. Basically counting calories just involves writing down everything you eat or drink. You can do this on paper or you can use the free online calories counter and tracking tools I recommended in the height weight tables article.

Calories to Maintain Weight

Everyday your body requires a certain amount calories to maintain weight. These calories are just energy to keep the blood flowing, the lungs pumping, and your body functioning. Depending on your normal daily workload the amount of energy required could vary greatly. Your body receives the calories to maintain weight it needs in the form of energy from food. You can think of a calorie as a unit of energy. Now if you have read anything about nutrition before I'm sure you have been drug into the debate of whether all calories are created equal or not. The answer really depends on your goals. If you are obese and looking for the calories needed to lose weight then you might as well assume a calorie is a calorie and it doesn't matter if it is from ice cream or chicken. Consume fewer calories than you burn and you will lose weight. If you are an athlete, bodybuilder, or working on that last 10 pounds of weight loss then all calories are not created equal and you need to monitor your macronutrient ratios more closely. For now we are looking at calories in versus calories out and keep it generic. Before we get into losing or gaining weight we firt must determine the calories to maintain weight

To Lose Weight you must burn more calories than you consume. To Gain Weight you must consume more calories than you burn.

Okay so how many calories to maintain weight?

The amount of calories to maintain weight your body needs each day can be calculated in numerous different ways using all kinds of inputs such as: your activity level, your weight, your height, your age, body mass index, base metabolic rate, or body fat percentage.

A quick method for determining your calories to maintain weight is to use your total body weight times a multiplier.

Calories to Lose Weight 12-13 calories per pound of bodyweight
Calories to Maintain Weight (TDEE) 15-16 calories per pound of bodyweight
Calories to Gain Weight 18-19 calories per pound of bodyweight

So if you weight 200 lbs and want to lose weight that would be 200 x 12-13 = 2400 – 2600 calories a day.

Now obviously this method is less than scientific and doesn't take into account body fat percentage, or activity levels. So for example a 50+ woman weighing 250 lbs with 40% body fat will not lose weight on 3,250 calories a day "diet".

A much better calculation would include your basal metabolic rate (BMR).

Basal Metabolic Rate (BMR) & Total Daily Energy Expenditure (TDEE)

Your basal metabolic rate is the amount of calories you body requires just functioning without taking into consideration your activity levels. The BMR multiplied by your activity level is the calories to maintain weight. The most popular formula is the Harris-Benedict formula but it does not take into account lean muscle mass. For most people this will work just fine but if you are extremely muscular you might find it underestimates your calories to maintain weight. On the same token if you are extremely overweight it will overstate your calories to maintain weight. The second formula based on your body fat is the Katch-McArdle formula. I will cover both but if you don't care and just want to use the online calculator, feel free to skip ahead.

The Harris-Benedict formula (BMR based on total body weight)

Men: BMR = 66 + (13.7 X wt in kg) + (5 X ht in cm) - (6.8 X age in years)

Women: BMR = 655 + (9.6 X wt in kg) + (1.8 X ht in cm) - (4.7 X age in years)


1 inch = 2.54 cm

1 Kilogram = 2.2 lbs


  • You are female
  • You are 30 yrs old
  • You are 5' 6 ” tall (167.6 cm)
  • You weigh 120 lbs. (54.5 kilos)

Your BMR = 655 + 523 + 302 - 141 = 1339 calories/day

Katch-McArdle formula (BMR based on lean body weight)

If you know your lean body weight (total weight - body fat percentage) due to a bodyfat caliper or at home body fat scale like discussed on the ideal weight page you can use the Katch-McArdle formula and get a more accurate TDEE.

TDEE = Calories to Maintain Weight

BMR (men and women) = 370 + (21.6 X lean mass in kg)


  • You are female
  • You weigh 120 lbs. (54.5 kilos)
  • Your body fat percentage is 20% (24 lbs. fat, 96 lbs. lean)

Your BMR = 370 + (21.6 X 43.6) = 1312 calories)

Once you know your BMR, you can calculate TDEE by multiplying your BMR by your activity multiplier from the chart :

Activity Level Description Multipler
Sedentary little or no exercise, desk job BMR x 1.2
Lightly active light exercise/sports 1-3 days/wk BMR x 1.375
Moderately active moderate exercise/sports 3-5 days/wk BMR x 1.55
Very active hard exercise/sports 6-7 days/wk BMR x 1.725
Extremely active hard daily exercise/sports & physical job or 2X day training, i.e marathon, contest etc. BMR x 1.9

Or you can use this daily calorie calculator to do all the work for you by just filling in the fields.

Age: (in years)
Activity Level:
Your Basal Metabolic Rate is:

Your Average Daily Calorie Need is:

Adjusting Your Daily Calories

So now we know exactly how many calories you need a day to maintain your current weight. If you want to change your body weight you are going to have to change the calories you take in or the amount of energy you use.

Gaining Weight

To gain weight it is pretty simple math. Eat more! If you currently lift weights 3 days a week and are eating your TDEE and want to add some weight then all you have to do is add in a protein shake a two a day and the weight will pack on. Another good recommendation is to drink a gallon of milk every day. Milk digests easily and contains lots of protein. Let's look at them both.

TDEE: 3,000 and lift weight 3 days a week.

Option 1:Adding 2 protein shakes a day

- 2 scoops of why protein = 400 calories (40 grams of protein) = 800 calories a day extra. That is an extra 5,600 calories a week!

- 2 scoops of why protein = 400 calories (40 grams of protein) = 800 calories a day extra. That is an extra 5,600 calories a week!

This is adding 800 calories a day with mostly protein. Assuming you are lifting heavy weights and giving your body plenty of time to rest you should be packing on the muscle fairly quickly (2-5 pounds a month).

Not working? Are you really getting 3,000 calories a day before the shakes? I bet not, be sure to track everything you consume on one of the tracking sites.

Option 2:Drinking a gallon of whole milk everyday

- - 1 gallon of whole milk is about 2,400 calories

I really think this one is enough said. In this example you would be almost doubling your calories to maintain weight. You are bound to gain weight quickly.

Be warned that we you start packing in the calories like this you are going to gain some fat too. That is not really a bad thing as you need the weight to lift heavy and pack on the muscle

Are you only working out three days a week? If you are doing cardio on your non-lifting days be sure to include how many calories you are burning during those sessions. You might be in a calorie deficit.

Losing Weight

Losing weight is pretty simple math too. A pound of fat weighs about 3,500 calories so in order to lose a pound of fat you need to create that deficit. So using the same example as above let's assume you have a TDEE of 3,000 and lift weights 3 days a week. You want to burn off 10 pounds of fat.

TDEE: 3,000 and lift weight 3 days a week.

Option 1:

Reduce your calorie intake by 500 calories a day. Try to do this by cutting carbohydrates instead of quality food. This is really pretty simple. You could have one less candy bar and soda, trim your portion sizes just a little bit, or cut your dinner in half.

500 calories a day for 7 days = 3,500 calories which will result in one pound of fat loss a week. You will achieve your goal in 10 weeks (2.5 months)

Option 2:

Reduce your calorie intake by 1,000 calories a day. Again do this by cutting carbohydrates instead of quality food. This is a little tougher but still not that hard. To tweak this far you have to take a close look at your diet and see what you can cut. Go through your calorie tracking tool and look to see where you can "trim the fat".

1000 calories a day for 7 days = 7,000 calories which will result in two pounds of fat loss a week. You will achieve your goal in 5 weeks (1.25 months)

How Low can You Go?

Men should always consume at least 1800 calories a day and women should always consume 1200 calories a day. Any lower than this and you risk doing internal damage or forcing your body into starvation mode (eats muscle instead of fat)

Great, that rounds out this section nicely and now we need to take a look at your goals, motivation, and emotional drivers. Basically, “Where do you Want to Go?”

gain 41 lbs of muscle in 24 weeks