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Unlock Your Weight Loss Potential With A Calorie Deficit Calculator

by | Dec 5, 2022 | Last updated Dec 15, 2022

Keto, intermittent fasting, CSIRO, paleo….  It can feel like everywhere you look, there’s a new diet that promises to be the secret to weight loss success.

Sure, it’s always a major win when you find an eating plan that your body responds well to, and that perfectly fits your lifestyle. But, when you get to the core of all effective diets, you’ll find they usually have one thing in common: They work because they involve eating less calories than you burn. 

Of course, they all use different paths to get there: keto involves eating only low-carb foods, while intermittent fasting restricts your intake to certain time windows. But when you strip them back, they operate on the same principle: putting your body into a calorie deficit.

What is a calorie deficit?

To lose weight, you must consume less calories than your body burns — this is what is called a calorie deficit.

When you consume fewer calories than your body burns, your body has to tap into its stored energy sources, such as fat, to make up for the deficit. This is what leads to weight loss.

Eating in a deficit of 500 calories per day will typically result in about half a kilo lost per week — research shows that this is a healthy calorie deficit to allow your body to function optimally while still losing weight.

To determine your calorie deficit and plan your weight loss journey, you can use a handy calorie deficit calculator. These calculators use your current weight, height, age, and activity level to estimate how many calories you burn in a day. From there, they can help you determine how many calories you need to consume to create a deficit and lose weight.

There are many different calorie deficit calculators available online, and they all work in slightly different ways. Some are more advanced than others, and some offer more detailed information and guidance. However, most calorie deficit calculators will provide you with a general guideline for how many calories you need to consume in order to create a calorie deficit and lose weight.

How Noom’s calorie deficit calculator works

To use a calorie deficit calculator, you’ll need to know your current weight and height. You’ll also need to know your age and activity level, as these factors affect your metabolism and how many calories you burn in a day. Once you have this information, you can plug it into a calorie deficit calculator to determine how many calories you need to consume to create a deficit and lose weight.

To find out how many calories you need to eat a day to lose weight, try Noom’s calorie deficit calculator. It uses your age, height, current weight, sex, and basic activity level to calculate the approximate number of calories your body uses in a day (your total daily energy expenditure or TDEE), based on the Harris-Benedict equation


Noom’s free calorie calculator estimates how many calories you need to burn to lose weight from your TDEE — while also eating a healthy number of calories to keep your body functioning at its best. This creates the Weight Loss Zone, which is a range of a few hundred calories. 

Eating closer to the lower end of the Weight Loss Zone typically leads to greater weight loss (about 1 kilogram lost per week), while eating at the higher end of the Weight Loss Zone leads to a more moderate weight loss (about 0.25 kilograms lost per week.)

free calorie deficit calculator

It’s important to note that you should be eating within the Weight Loss Zone — not below it. Your body needs calories to function properly. Going below your zone can lead to headache, fatigue, a weakened immune system, and slow your metabolism down. Not fun! Plus, it isn’t sustainable in the long term. 

If you’re new to tracking your calories, starting at the higher end of the Weight Loss Zone might feel like a more flexible and realistic place to start. If you plan to log your meals and track calories consistently, you should gain more confidence in staying within your range.

While based in science and research, this calorie deficit calculator is more of an estimate and doesn’t account for other lifestyle factors that might impact your calorie needs. 

For example, if you have an increased activity level or are lactating, it’s recommended that you take in more calories. Please chat to your GP before embarking on a weight-loss plan, especially if you’re lactating — calorie needs vary based on lactation intensity.  

How Noom can help you lose weight with a calorie deficit

Noom can help you lose weight by recommending a calorie target to shoot for, which also accounts for daily activity — you can use your phone as a pedometer to track steps or connect a smart device like a Fitbit or Apple Watch. Plus, for every calorie you burn, you’ll get half a calorie back — which means more room for your favourite foods (chicken schnitty burger, anyone?)

Noom Weight will also help keep you on track with a structured system that combines psychology-based lessons, a colour-coded food system, and other tools for sustainable long-term weight loss.