Sometimes it’s obvious that you’ve strayed from a healthy weight: The number on the scale at your gym is 5 pounds higher than it was six months ago, or it’s become a wrestling match just to button your favorite pair of jeans.

So how do you know what’s a healthy weight to aim for? There are three handy tools that can help assess your weight and let you know if you land in the healthy range:

One way to tell if you’re at a healthy weight is by finding out your BMI (body mass index). BMI is by no means perfect. Some argue that it’s too simplified to be truly accurate. For example, athletes who are muscular with little fat may rank as obese since muscle weighs more than fat, driving up their weight even though they may be incredibly fit.

But let’s be honest: Most of us aren’t elite athletes who are so fit that they can’t even pinch an inch of skin. So instead, think of BMI as a ballpark tool — and for some, a wake-up call — to assess whether your weight is in the healthy range, or if you need to make some changes to lower that number. Use this tool to find out your BMI.

Once you have your number, you can compare it against the Centers for Disease Control and Prevention‘s scale:

• If your BMI is less than 18.5, it falls within the “underweight” range.

• If your BMI is 18.5 to 24.9, it falls within the “normal” or Healthy Weight range.

• If your BMI is 25.0 to 29.9, it falls within the “overweight” range.

• If your BMI is 30.0 or higher, it falls within the “obese” range.

Waist circumference:
The circumference of your abdomen can indicate whether you’re overweight and possibly putting your health at risk. That’s because carrying around excess abdominal fat is linked with several health problems, including type 2 diabetes, cardiovascular disease and high blood pressure. These health risks are higher in women with a waist that is greater than 35 inches (or greater than 40 inches for men), according to the National Heart, Lung and Blood Institute. To find out what your waist circumference is, stand up and place a flexible tape measure around your waist, just above your hipbones. Exhale and measure your middle. 

Waist-to-hip ratio:
Finding out your waist-to-hip ratio (WHR) can also shed some light on your health. Here’s how to do it: Grab some flexible measuring tape and measure the circumference of your waist (at the smallest part of your torso, usually just above your belly button), and then measure the circumference of your hips (at its largest part around the buttocks). Next, divide your waist number by your hip measurement.

You can find out what your waist-to-hip ratio is here. To give you an idea of how your number stacks up: The ideal WHR ratio is between 0.65 and 0.75. Having a waist-to-hip ratio that’s greater than 0.75 is associated with a higher risk of health problems, including type 2 diabetes.

If these tools show that you’re in the overweight or obese range, talk with your primary care physician about setting a realistic weight loss goal, such as losing 1 or 2 pounds per week. This isn’t about crash dieting or starving yourself. Losing weight in a healthy way means making choices you can stick with long term, even if it’s making them one at a time, such as giving up diet soda, cutting down on the amount of sugar you consume, or working vegetables into every meal. Over time, even these small changes can add up to big losses on the scale and a healthier weight.

READ MORE: 10 Science-Backed Ways to Lose Weight