BMI Calculator

The BMI calculator is a useful tool, it allows us to see whether our weight puts us at any health risk and it helps us choose a target weight for our slimming campaign.

You can work out your BMI without a BMI calculator, by dividing your weight (kg) by your height (m) squared!  But why bother when Slimming World’s BMI calculator is free for anyone to use. 

And don’t panic if you don’t know your weight in kilograms or height in metres, our BMI calculator also works in feet and inches, stones and pounds!

It’s all well and good calculating a figure, but what does it mean?  Whatever your BMI, our BMI calculator will give you the result in figures, advice on what that means and help you find a local Slimming World group if you’d like the support of one of our caring Consultants and the friendship of a group of like-minded people to help you achieve a healthy weight.

What's a healthy BMI?

As you’ll find out from our BMI calculator, a BMI of 20-25 is considered a healthy weight.  A figure above that suggests you may be at risk of developing weight-related problems. A BMI of below 20 indicates that you could be underweight and losing more weight could also be detrimental to your health.

After a BMI check at her local well-woman clinic, Nicola Smith was told she was ‘obese’. 

My fiancé and I both tried to lose weight with the Atkins diet and the GI plan, but these plans weren’t practical for our lifestyle. When a flyer for Slimming World floated through our letterbox, we went along and have never looked back!

Nicola lost a brilliant 1st 11½lbs and achieved a healthy BMI in time for her September wedding. “I can't tell you how much better I feel for joining Slimming World!” Nicola told us. “The group we attend is amazing, the support and warmth that they give is overwhelming!”

So try Slimming World’s BMI calculator today and know that, if you need our help and support to lose 7lbs... lose a stone... or lose more, we’ll be with you every step of the way.

Please note

The BMI caculator is not suitable for people with an extremely high muscle mass, mums to be or under 16s,

Although our online BMI calculator isn’t suitable for 11-15 year olds, young members can still join Slimming World groups. Your Consultant has a special BMI calculator wheel in group that will calculate your BMI.  With the support or your parents and guidance from your GP/nurse, your Consultant will help you discover new, healthy eating habits and make cool swaps to lead a healthier, fitter life

Discover more about our easy way to lose weight, then find all the support you need at your nearest warm and friendly Slimming World group.

Find a group in your county

Search for a group

or become an online member

You'll find more delicious recipe and menu ideas at your local group, along with all the help you need to get started and reach your target weight.

What you get with group membership

  • A friendly, understanding Consultant – who’s been a member themselves
  • Image Therapy – the heart of a Slimming World group – giving you unique help, support and encouragement when you need it most
  • Loads of praise and celebrations for each weight loss milestone you achieve
  • Warmth, friendship, laughter, sharing ideas, recipes, inspirational stories and much, much more
  • Free access to dozens of online features and tools to support you between groups
find a friendly local group

What you get with online-only membership

  • Weekly online support and motivating e-mails based on your personal progress
  • Access to motivational support tools, insightful features and special strategies to help you in the weeks ahead
lose weight online

Featured success

I’m loving the good life
I’m loving the good life

At over 20st, Emma found it hard to care for her beloved pets. Now she’s 8st 10lbs lighter and has lots more energy for her family of animals!

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