//Weight loss calculator – calculate body fat percentage
Weight loss calculator – calculate body fat percentage2018-08-19T12:17:44+00:00

Weight loss calculator – calculate body fat percentage

It will calculate your Basal Metabollic Rate (BMR), Body Mass Index (BMI) & calculate body fat percentage – all in one go!

Find out your BMI, BMR, maintenance calorie needs & calculate body fat percentage – all in one handy weight loss calculator.

This is an advanced weight loss calculator, since it’s three calculators in one. It’s a BMR, BMI and a body fat percentage calculator. Use it to find out your body composition and calorie needs. The results will help you see how the calories you eat and the calories you burn through exercise, affect your body.

Because we’ve built this clever calculator to give you a head start in your weight loss planning. So, get your weight scales and tape measure handy, and see just how fat you really are.


Your BMI, BMR, calorie needs & fat percentage - pretty much all you need to get that weight loss plan together!

3Hip (Female):

Not sure which to choose? Scroll down the page for details



Very little or no exercise


Do you sit all day at a desk? or could you win Mastermind with daytime TV as your specialist subject? If so, it’s likely you lead a sedentary lifestyle.

Lightly active

light exercise/sports 1-3 days/week

Lightly active

Do you walk to the shops and do the housework? or even pop to the school gates twice a day? You may be busy, but you’re still only lightly active.

Moderately active

Moderate exercise or sports 3-5 days a week

Moderately active

Do you go to the gym, on a brisk 1 hr dog walk or dance till you drop 3 times a week ? Then it’s likely you’re moderately active.

Very active

Hard exercise or sports 6 to 7 days a week

Very active

Do you exercise in the gym, walk briskly or jog with the dog every day and still remain active the rest of the day?  – You’re active!

Extra active

Very hard exercise or sports & a physical job or hard training

Extra active

Okay so we know this probably isn’t you (or us for that matter), but for the sake of completeness; very active people move – they move fast – and they move a lot! They might be a brick layer by day and a gym fanatic by night. Or a gardener by day and a jogger training for their next marathon. Oh yes and they do it all while fitting all the other stuff the rest of us do each day in as well!

Do you want to know what Body Fat Percentage is?

Body fat percentage is just the proportion of your body weight made up of fat tissue.
Because body fat percentage often impacts fitness levels, it can be a better signal of health than BMI.

As a result, we developed the body fat percentage calculator so you can measure your progress.

How using our weight loss calculator to calculate body fat percentage can help weight loss

If you know your body fat percentage, you know how many pounds of fat you have too. This helps you set realistic and healthy weight targets.
Also, your body fat percentage helps calculate a correct TDEE (total daily energy expenditure). Because calculators use average body fat percentages, if your BF% isn’t average, your results will be inaccurate.
Most of us on a diet want to reduce our fat mass while increasing our muscle mass. Seeing changes while you’re dieting is a great way to track progress. So it’s probably worth using our body fat percentage calculator regularly.

Having Body Fat is Healthy

Having some body fat is healthy. And your body needs fat tissue to regulate hormone production and body temperature. Don’t let it get so low that it results in a risk to your health. Especially if it’s less than the levels experts advise.

What percentage body fat should you have?

This table by ACE shows both male and female classifications based on body fat percentage.

Type of fat / descriptionWomenMen
Essential fat10–13%3–6%
Very lean14–20%7–13%
Obese40% or more30% or more
weight loss calculator calculate body fat percentage

What is BMI?

BMI or Body Mass Index is a measure of body fat based on weight in relation to height. It is one of three elements this weight loss calculator works out.

So what is the normal BMI?

Compare your BMI to your peer group in our ideal BMI chart. It may be better than you think. Of course, if it’s not, that’s another reason we’re here. We’ll explain why and help you achieve your weight loss target. If you want more detailed information on BMI, click here.

ideal BMI chart

What is BMR?

Basal Metabolic Rate (BMR) is the total calories your body needs to perform basic functions like breathing. It’s an essential piece of the weight loss calculator jigsaw puzzle, which will also calculate body fat percentage and BMI.

The difference between BMR and Resting Metabolic Rate (RMR)

Many weight loss and exercise guides use the terms BMR and RMR. Now, these terms are very similar, but there is a slight difference between them that’s useful to understand too.

BMR is a measurement of the number of calories needed for your body’s most basic functions, like breathing. Hence the most accurate way to measure it is in a laboratory.

In comparison, RMR is a measure of the calories your body burns while at rest. And it’s usually measured in the morning before you eat or exercise.


As you can see RMR and BMR are almost identical. So, your resting metabolic rate should be an accurate estimate of your basal metabolic rate.

Because they’re so similar, many fitness and weight loss experts use either when referring to the same thing.

Reasons to use our weight loss calculator to calculate your BMR

Just knowing your BMR isn’t as useful as knowing your BMI and how to calculate body fat percentage too. And once you know more about your body, you can plan your diet more effectively. So, give it a try, use our all in one weight loss calculator now.

Compare other Body Fat measures and methods

Here are some other tests that calculate body fat percentage. But we’re sorry, you’re on your own for these–as there aren’t any clever online calculators involved.

Immersion Test

So far the best way of measuring of body-fat is the immersion test. When you take the test, you’re (as the name suggests) immersed into a pool. And its error rate is just 1 percentage point. You’ll find it at hospitals and a few gyms, but it’s very tiring and can last up to 60 minutes. We could only find commercial locations offering this test in the US for example Body Fat Testing. But it’s expensive and how many visits would you need to get motivational results?

Bod Pod

A next generation body fat measuring tool that is precise and painless. Whereby you step into a pod, sit for 20 seconds, and that’s it. Air displacement, is converted to relative fat when weight is factored in is measured. Early tests show it’s equal to immersion. It can be found at only a few hospitals and universities. But it’s quick and easy at £40 a go it’s not so pricey either and we found it in the UK at the University of BCOM.

Body composition tests vs. our online weight loss calculators

Body Fat Pinch Test vs. weight loss calculators

You can use calipers to measure & average folds of skin & fat in places on your body. But it’s not a precise method – you do need to be very accurate, you can either go to a professional at a gym. Or try it yourself right now by following our instructions & using our body fat percentage calculator

Bioelectrical Impedence Analysis (BIA) vs. our online weight loss calculator

Electrodes are attached to your hand & foot, a radio-frequency pulse is run through your body to measure water content. That provides a guide to calculate body fat percentage with an error of 2 or 2 1/2%. But anything that affects your hydration, such as exercise or drink before the test can impact results.

BIA at home

Nowadays, you can buy paired down versions of these for use at home in the form of weight scales.

But these scales determine body composition by sending currents up one leg and down the other. That means Impedance is only actually measured for the legs.  In contrast to the real thing, to calculate the upper body fat percentage, scales make assumptions. And the assumptions are based on the composition of your legs (and if using age and gender data, adjusting for those as well).

So, if you have hefty thighs and skinny shoulders or are a V-shape or A shape (see our body type calculator) your results will be inaccurate to say the least!

BIA scales are becoming one of the most popular ways to calculate body fat percentage and body composition. Thi is because of their speed, convenience, and accuracy. And there’s no shortage of them to buy, and costs range greatly. Some are under £50, while others range in the tens of thousands.


All the weight loss, calorie, fat burning, BMI, BMR and diet planning calculators you’ll ever need.

All free and all in one place!

Not only that, our weight loss planner factors in how your metabolism really works to predict how long it’ll take to reach a particular weight loss goal.


From the Atkins diet to the South Beach diet and from low carb to low fat diets, you’ll find them here.

Check out the differences between the diet types and find out what we think works.

Anni’s Blog

I’m Anni, I’ve lost over 55lbs in weight and admit it’s been a life long struggle. Now at 50 +, I’m sharing what I’ve learned along the way.

Read my weight loss blog for tips, tricks and insights into staying motivated on the weight loss journey.