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Calorie Calculator

To lose weight, you need to eat fewer calories than your body burns every day. This is why figuring out how many calories you should eat is one of the most important steps to losing weight. Use our simple calculator below to estimate how many calories you should eat every day based on your goal.

Calorie Calculator FAQ

How do I calculate how many calories I need to eat?

Our calorie calculator does all the math for you once you complete these 3 steps:
  1. Choose your preferred unit of measurement for mass (i.e., LBS or KGS)
  2. Input your gender, weight, activity level, and body percentage (feel free to check out our gender-specific body fat percentage charts if you’re not sure of this)
  3. Finally, click on the button “SHOW MY RESULTS”
And almost immediately, you’ll learn how many calories you need to eat to:
  • Maintain your weight
  • Lose weight (broken down into the calories you should eat for 3 weight loss rates — slow, moderate, and fast)
  • Gain weight (also broken down into the calories you should eat for 3 weight gain rates — slow, moderate, and fast) 

How many calories should I eat a day to lose weight?

You’ll need to eat fewer calories than your body burns (i.e., your total daily energy expenditure or TDEE) to lose weight. 

Your TDEE depends on many factors, including your sex, weight, and physical activity level. To minimize muscle mass loss, a weight loss rate of 0.5% to 1% of body weight per week is an excellent target to strive for. Generally, those with a higher body fat percentage can afford to take a more aggressive approach to weight loss than leaner individuals without risking as much muscle mass loss. 

Your target rate of weight loss would then guide you on how many calories you should eat daily. To illustrate how that works, let’s say you weigh 140 pounds (63.50 kilograms) and aim for a modest weight loss rate of 0.5% — which translates to 0.70 pounds or 0.32 kilograms — per week. Assuming there are ~3,500 calories in a pound (or 0.45 kilograms), you’d need to create a calorie deficit of 2,450 weekly, or 350 calories daily. 

Feeling the beginnings of a massive headache from all those numbers, percentages, and calculations? No worries. Our Calorie Calculator’s got you covered. Check out “How do I calculate how many calories I eat?” to learn how you can use it. 

What exercise burns the most calories?

If you want to burn the most calories within a workout session, your best bet would be cardio (versus strength training when the duration is matched). 

That’s because research shows lifting weights just isn’t all that good at burning calories, especially compared to traditional cardio forms. And contrary to popular belief, “traditional forms of cardio” doesn’t mean the same as “cardio forms that most people find torturous”, like running. 

It could be something as simple as walking. Yes, really

And I’ve written several articles on why I think walking is the best and easiest exercise to lose fat faster — with this being the latest article.

Now, don’t be mistaken. I’m not saying that strength training does nothing for burning calories. In fact, it’s quite the opposite. While it does burn fewer calories compared to cardio, consistently lifting weights can help you put on muscle mass, which:

  • Increases the number of calories you burn at rest and during physical activity, and
  • Improves appetite regulation 

Both are important factors for successful long-term weight management. But, of course, you could make certain tweaks to your strength training sessions to maximize your calorie burn; find out what those are in this article.

What’s the best calorie tracking app?

Once you find out how many calories you should eat to lose weight or gain weight, the next step is to start tracking your calories. We suggest taking slow steps towards reaching your new calorie target. For example, if you’re currently overeating, then try to reduce your calorie intake by ~100 calories at a time until you’ve reached your target. 

As for the best calorie tracking app, we generally recommend MyFitnessPal or LoseIt. Cronometer is a good option as well if you’d like to go beyond just calories and see if your diet is meeting your minimum vitamin/mineral intake requirements as well.

However, the downside with these calorie tracking apps is that it doesn’t adjust your calorie intake based on your progress. When you first start a diet, you may require a certain amount of calories to lose weight. But once you’ve lost some weight, your body starts to adapt to this. It’s why many people see some success initially but eventually get stuck.

This is why we’ve created our own Built With Science nutrition software. It not only provides you with a recommended amount of calories to start your diet with, but it keeps track of your progress and will adjust your calories over time to prevent you from ever getting stuck. It takes care of all the guesswork for you.

This software is included in every single one of our Built With Science programs. You can find what program is best for you and your body by taking our 30-second quiz here.

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