From my experience a lot of people hesitate to even try and lose weight because they don’t know from where to start. They know that they should go on a diet and exercise regime but the lack of measurable goals creates uncertainty and this leads to failure before to even begin!
To bypass this problem and have clear goals on what you want to achieve, you can start your weight loss process by doing some simple calorie calculations.
By calculating how many calories you should be eating per day and how many calories you should be burning per day, you can have a better picture about your daily calorie needs and a rough estimate as to when you will be able to reach your ideal weight.
Before getting into the mathematical part let me explain some basic weight loss concepts that will help you understand what these numbers mean.
You do not have to keep a pen and paper because our daily calorie calculator will do the hard part.
When do you lose weight?
There are many factors that affect how much weight you can lose (and when) but in its simplest form weight loss will occur when the calories you burn are more than the calories you consume.
Food and drinks (think diet) are the only sources for calories you consume while exercise, physical activity and other body factors affect the rate you burn calories.
So, if you manage to control these 2 sources and create a calorie deficit you will eventually start losing weight.
How many calories are in a pound?
Let’s add one more parameter to our equation which is 1 pound of fat = 3500 calories aprx.
This means that if you consume 3500 more calories than what you burn in a period of time you will gain one pound but if you manage to burn 3500 more calories than you consume you will lose 1 pound.
What is my daily calorie requirement?
Many studies have found that in general women need 1500-2000 kcal to maintain their current weight and for men the range goes to 2000-2500 Kcal.
This number is also known as the Basic Metabolic Rate (BMR). In essence this figure gives you the number of calories your body needs on a daily basis in order to function properly.
Note: This is not how many calories you consume per day but how many calories your body needs to function.
BMR and Daily Calorie Calculator
You can use our BMR calculator above to find out your basic metabolic rate which is based on your weight, age, height and daily activity.
We will use BMR to calculate how many calories you should be eating per day and then demonstrate with an example how many calories you should burn per day if you want to lose weight in a specified amount of time.
Daily calorie needs to maintain current weight = BMR x Activity Factor
Note: You do not have to take a calculator to make the equation; you can use our daily calorie calculator above.
|Daily Activity||Activity Factor|
|Sedentary (little or no exercise)||1.2|
|Lightly Active (light exercise, doing sports 1-3 days per week)||1.375|
|Moderately Active (sports/exercise 3-5 days per week)||1.55|
|Very Active (intense sports 6 or 7 days per week)||1.725|
|Extra Active (sports and exercise, physical job or hard training)||1.9|
For example, if your BMR is 1600 and you are lightly active during the day then your daily calorie requirements are: 1600 x 1.375 = 2200 kcal per day. 2200 calories are needed so that you maintain your current weight.
If you want to lose weight you should be consuming less than 2200 calories per day and if you want to gain weight you should be consuming more than 2200 calories per day.
How many calories to eat if you want to lose weight?
Before getting into a real example of how to calculate the calories you should be eating per day for weight loss let me say that this is only an estimate and it is not guaranteed that by following this number you will lose or gain weight.
There are many other factors involved in losing weight and the number of calories you consume is just one of the elements and since it is easy to calculate you can use it as your starting point.
Let’s assume that you need to lose 5lb in 2 months, this is how you calculate the amounts of calories to eat per day:
Step 1: Calculate your BMR and daily calorie needs
After using our BMR and daily calorie calculator you found that: BMR is 1800 calories and daily calorie needs are 2000 kcal.
Step 2: Calculate the calories you want to lose
You want to lose 5lb which is aprx 17500 calories (1lb of fat is 3500 calories)
Step 3: Calculate how many calories you need to save per day
Your goal is to lose 5lb in 2 months. Doing some basic calculations you can find out that 17500 calories in 2 months is about 8750 calories per month or 2187 per week or 313 kcal per day. So in theory, if you manage to save 313 calories per day you will lose 5lb in 2 months
Step 4: Subtract the number of calories you need to save per day (Step 3 above) from your daily calorie needs (step 1 above)
Daily Calorie needs – Calorie savings per day = 2000 – 313 = 1687 kcal per day. This is the number of calories you need to eat per day if you want to lose 5lb in 2 months!
How many calories to burn per day if you want to lose weight?
Since you know the number of calories you should be eating per day, you can use a calorie counter to calculate the amount of calories you actually eat (or drink) on a daily basis and find out the amount of calories you need to burn via exercise if you want to lose weight.
Hint: You can use our Free Calorie Counter to keep count of your meals and activities.
For example, if you are consuming 1800 calories per day and in order to lose weight you need to consume only 1687 calories per day (as calculated above) then this means that you should burn 113 kcal per day by doing exercise.
What you should know when doing your calculations
- When you start a diet or weight loss program you will not only lose fat. Especially at the beginning you will lose water weight and in some cases you may also lose muscle. So the results in the first few weeks may be misleading.
- When you make sudden or drastic changes to your diet the body will try to adapt by lowering the metabolic rate. In other words it enters a protective mode by reducing the number of calories it needs per day. As a result weight loss may slow down, here is how to lose weight and keep it off.
- The absolute minimum amount of calories you can consume per day is 1000-1100 kcal. It is not recommended to go beyond this number for any reason.
- The recommended weight to lose per week is between 1 – 1.5 pounds. Anything above that can have other implications to your health and normal body functioning.
- Do not forget that drinks also carry calories so make sure that you include drinks in your daily calorie calculations. You can read our article on the 5 best healthy weight loss drinks that work to find out which drinks are ‘weight loss friendly’.
- You can use a technique called “calorie cycling” to make the process easier to follow. This means that once you calculate your daily calorie needs you can go above and below this range on different days of the week. If for example you daily kcal needs are 1700 you can choose to go above this number on Monday and Wednesday and below this number the rest days of the week but try to avoid exaggerations. You can also read about carb cycling to access if this is something you want to try for your diet.
- Make sure that you give correct measurements for your weight and height when calculating your BMR.
- Do not lie about your activity level but try to be as accurate as possible.
- Do not decrease your daily calorie intake by more than 500 kcal per day. Better expand the time period. Reducing your intake by 500 kcal is a lot and very difficult to follow for a long time.
- Always consult your doctor or dietician before making any changes to your diet or exercise routine.
As explained above you can use these calculations to give you an idea where you stand and how much effort you need to make until you meet your goals and target weight.
Weight loss depends on a lot more factors and calculating the calories you need per day is just your starting point.