Work out how much weight you need to lose
Use the BMI calculator above to work out how much weight you need to lose before starting the NHS weight loss plan.
The BMI tool will tell you if you're in the healthy weight range and, if necessary, how much you need to lose to achieve a healthy weight.
Ideally, you should aim for a target weight that gives you a BMI in the healthy weight category for your height (18.5 to 24.9).
The BMI tool will also provide you with your own personal "daily calorie intake" to help you lose weight at a safe rate.
Having a weight loss goal to work towards is a useful way to stay focused and motivated on your weight loss journey.
Once you've worked out your weight loss target, download week 1 of the NHS weight loss plan (PDF, 1.26Mb), a 12-week diet and exercise guide.
If you have lots of weight to lose, losing enough weight to achieve a healthy BMI may seem pretty daunting.
Some people like to set themselves small weight loss goals to stay motivated as they work their way towards their overall target weight.
When trying to lose weight, it's tempting to want fast results. But studies show people who lose weight too fast end up putting it back on again.
The NHS weight loss plan is designed to help you lose weight at a safe rate of 0.5kg to 1kg (1lb to 2lb) per week by sticking to a daily calorie allowance of 1,900kcal for men and 1,400kcal for women.
Unless done under medical supervision, losing weight faster than this can increase the risk of health problems, including malnutrition and gallstones. It can also make you feel tired and unwell.
Find out about getting started on the NHS weight loss plan.