Seeing the number go down on the scales is a great feeling, but kilos and stones don’t tell the full story. The same amount of weight loss can mean something completely different depending on where you started. When you work out your weight loss as a percentage of your starting weight, you get a clearer view of how your progress truly impacts your health.

In this guide, we’ll show you exactly how to calculate your percentage weight loss and include a simple calculator so you don’t have to work anything out yourself. We’ll also explain what your result really means for your health in real terms, so you can see the impact your progress is already having.

Three key takeaways

• Tracking weight loss by percentage gives you a clearer picture of just how much weight you’ve lost.
• A weight loss of 5–10% can help improve blood pressure and blood sugar levels and reduce the risk of several weight-related health conditions.
• You can use our calculator to see your progress instantly.

Why tracking percentage loss matters

Clinicians often use the percentage of body weight lost to monitor progress in weight loss and obesity. Most medical studies also use percentage loss rather than total kilograms or pounds because it allows the results to apply to people with different starting weights.

Watching the number on the scale can still be motivating, but it doesn’t always tell the whole story, especially when it comes to improving blood pressure and blood sugar levels and reducing health risks. That’s where percentage tracking is more informative for both you and your clinician.

It’s also worth remembering that your weight can naturally fluctuate by 0.5–1 kg (1–2 lbs) daily. For many people, this can feel discouraging. Tracking your progress as a percentage of your starting weight helps you focus on the bigger picture rather than small daily changes.

Calculate your weight loss percentage:

How to calculate your weight loss percentage

We calculate your weight loss percentage using a simple formula. This is:

(Your Starting Weight - The Weight You Are Right Now) ÷ Your Starting Weight × 100

We'll walk you through how this would work using an example.

1. Let's say your starting weight was 99.79 kg, or 15 stone 10 lbs, and you now weigh 87.09 kg, or 13 stone 10 lbs.
2. You work out the first part of the formula by taking 87.09 kg (your most recent weight) from 99.79 kg (13 stone 10 lbs). This gives you 12.7 kg (2 stone).
3. This means you've lost 12.7 kg (2 stone). Now you can work out the percentage.
4. 12.7 kg (2 stone) divided by 99.79 kg (15 stone 10) is about 0.127.
5. 0.127 times 100 brings you to the final result: You’d have lost 12.7% of your body weight in this example.

But we’re not here to make you do math, so you can use our calculator, which does it all instantly.

What is a healthy weight loss percentage?

Losing around 5-10% of your body weight, depending on your starting weight, over three to six months is realistic and considered a healthy weight loss percentage. This can make blood pressure and blood sugar better in people who are overweight or obese. It can also lead to:

• Better diabetes control (if you have it)
• Taking less medicine to manage diabetes
• A lower risk of stroke and heart disease
• More energy
• Improved movement and less strain on your joints
• Increased confidence
• Reduced anxiety

Saying this, people living with obesity might start to see a health boost after losing only 3% of their original body weight. But doctors use 5-10% as a guideline when they’re helping you with weight loss.

During treatment, you may also lose more than 10% of your body weight. Depending on your starting weight, continued weight loss beyond this point can lead to even more health benefits, especially for blood pressure, blood sugar and cardiovascular risk. However, it’s important that weight loss stays within a healthy range.  Your clinician will help ensure your progress remains safe and appropriate for your body.

Why use a percentage instead of a number on the scales?

Tracking your weight loss as a percentage can help you focus on meaningful progress, rather than chasing a single number on the scales. Setting a goal based on percentage loss can feel more personal and realistic.

Everyone starts from a different weight and has different health needs.
Losing 1 stone is a great achievement, but its impact on your health depends on your starting weight.

• If you start at 95 kg (15 stone) and lose 6.35 kg (1 stone), your body has gone through a significant change.

• If you start at 160 kg (25 stone) and lose the same amount, it is still progress, but the percentage of body weight lost is smaller, which means the health impact may not be the same.

This is why percentage tracking gives a clearer picture of your progress.

Resources for tracking your weight loss

There are many apps, trackers, and services that can help you monitor your weight loss journey.Weighing yourself can sometimes feel daunting, so logging your weight as you go can help you stay on track.

• NHS Weight Loss Plan, which features a daily progress journal and a weekly weight logging tool that calculates your progress for you
• NHS Digital Weight Management Programme (DWMP), which your GP or pharmacist needs to refer you to, but requires that you weigh yourself and log the results

Writing down what you eat and the exercise you do can also help you make healthier choices as you lose weight. This can all give your clinician a picture of what’s working and where you could use some extra help.

Also, bear in mind that while numbers on a scale and percentages are helpful, they aren’t everything. Check in with yourself about other wins:

• Do your clothes fit better?
• Can you walk or run for longer without getting out of breath?
• Do you feel more confident and less anxious?
• Are your blood pressure and blood glucose getting better?

Combining info like this with your body weight percentage can give you a clear picture of your progress and spur you on to achieve your health goals.

Frequently asked questions

• Should I track kg lost or percentage lost?

You can track weight loss in the way that feels most comfortable. Knowing the number you’ve lost on the scales and a percentage can give you the clearest picture.

• Can I regain a little and still be in a healthy percentage range?

That depends on your starting weight. Your weight will naturally go up and down day-to-day. For example, if you lose 10% but regain 1%, you’ve still lost a percentage of body weight that really improves your health.

• Is 5% really enough to make a difference to my health?

Yes. Plenty of research backs the blood pressure, blood sugar, and heart health benefits of losing even 5% body weight.

Sources

• How to achieve a healthier weight. (n.d.) British Dietetic Association. [Accessed on October 16th, 2025]
• Lose weight. (n.d.) NHS. [Accessed on October 16th, 2025]
• Treatment: Obesity. (2023) NHS. [Accessed on October 16th, 2025]
• Weight Fluctuations. (2020) NHS. [Accessed on October 16th, 2025]
• Weight management. (n.d.) NHS. [Accessed on October 16th, 2025]