Your body is a hangry beast — one that needs to be fed occasionally, regularly, or all the damn time, depending on its natural hunger cues.

Whatever your “healthy weight” is, if your body’s cues are off (or if you’re dealing with a chronic condition or illness), it can lead to a weight that’s lower or higher than your healthy weight range — one that you or your doctor feel won’t allow you to nourish and flourish.

Healthy weight maintenance, loss, or gain is less challenging when you’re armed with some numbers to act as a mental goal post.

Enter the calorie calculator to help you customize the process. Input whether you want to maintain or lose weight to calculate your optimal daily total.

The calculator above uses the Mifflin-St. Jeor equation, regarded as the most effective measure of a person’s basic energy needs, based on “resting metabolic rate (RMR).”

FYI: Adapting your calories to gain healthy weight may require a chat with your doctor, especially if you’re pregnant or recovering from an illness or eating disorder.

Having an idea of how many calories your body needs is a good first step toward feeling informed and confident about making healthy choices.

Remember:

You’re calculating an estimation of your calorie needs. Calorie counts on packaged foods are often slightly off, and factors such as a lack of sleep can affect how your body holds onto weight over time, even if you’re sticking to your estimated caloric intake.

So don’t obsess over counting; think of it as more of a general guide.

Also, counting calories isn’t a good idea for everyone. If you have a history of disordered eating, it’s something you should only consider after a heart-to-heart and OK from your doctor.

The Academy of Nutrition and Dietetics recommends that “moderately active” adult women aged 19 to 30 consume 2,000 to 2,200 calories per day. Sedentary women might only need 1,800 calories per day, and active women might need 2,400 calories per day.

According to the U.S. Office of Disease Prevention and Health Promotion, “active” means those who perform physical activity equivalent to walking 3 miles per day.

Men in the same age range who don’t exercise should take in 2,400 to 2,600 calories, and 2,600 to 2,800 if they’re moderately active. Active men might need up to 3,000 calories per day.

That’s the average, but there are plenty of variables, so… what about me, you ask?

Research suggests that smartphone calorie tracking apps are effective tools for people trying to monitor their weight.

Here’s a look at some fast-food brands using tech to help you demystify their menus and track your food intake.

The Subway calorie counter: For sandwich savoir faire

Subway delivers more than just tasty combos and addictive Southwest Chipotle sauce.

Plug in your order — down to every condiment, topping, and side — via the Subway calorie calculator (developed with the help of registered dietitians) to find out calorie, fat, and carb info.

The Chipotle calorie counter: For avoiding burrito bummers

The Chipotle calorie calculator provides basic nutritional data and all the deets on allergens like soy, sulphites, and gluten content.

The Lose It! calorie app: For winning at losing

The Lose It! calorie counter app puts a database of more than 7 million foods at your fingertips for convenient tracking anywhere.

The app lets you track your workouts and even connects you with community members for activities and challenges. The premium version ($40 a year) includes a sleep tracker.

Add these simple lifestyle changes to the mix and you can put weight management on autopilot.

1. Go pro(tein)

From paleo to keto, it’s hard to ignore the buzz on diets that emphasize protein and de-emphasize carbs.

Researchers praise protein for its usefulness in weight control. It can fill you up for longer so you’re less likely to consume extra calories.

A 2010 study concluded that high protein diets increase energy expenditure, or calorie burn.

Some experts caution that the sources of your protein are important, meaning your meals shouldn’t look like Oktoberfest every day.

Your heart health and blood pressure could take a beating if you go overboard on sausage and red meat, which contain a ton of fat and sodium. Skinless chicken and salmon are healthier alternatives.

2. Pump up your volume

It’s a myth that strength training will cause you to bulk up like The Rock. Lifting weights can actually make you smaller by curbing belly fat and boosting your metabolism.

A Harvard study found that men who lifted weights for 20 minutes per day had smaller waistlines when compared to men who did moderate to vigorous cardio instead.

A 2010 study showed that women who pumped iron avoided gaining visceral fat, or internal fat on the abdominal muscles.

However, the researchers found no difference between the women who lifted weights compared with women who did cardio exercise. Both forms of exercise had a positive effect on belly fat prevention.

Weight training also appears to boost metabolism, so you burn more calories while sitting around (it boosts your resting metabolic rate, or RMR).

3. Remote down, heart rate up

Cardio tops most people’s weight loss to-do list. If you consider the simple equation that to lose weight, you need to burn more calories than you consume, torching calories with sprinting, aerobics, or [insert strenuous activity here] are a no-brainer.

Cardio exercises such as hiking, walking, biking, and dancing are good for your heart. Aerobic exercise helps your body use oxygen more efficiently, meaning it improves stamina and boosts energy levels.

Add strength training to your cardio mix for an added metabolism boost. It helps build muscle, which burns more calories, making it easier to lose and control your weight long term.

4. Be less cordial to carbs

The keto diet is a high fat, low carb diet that’s been shown to be an effective way for people to slim down while not feeling hungry.

A study published in The American Journal of Clinical Nutrition supported the high fat, low carb diet’s ability to curb appetite and keep energy levels up.

And a small study concluded that a low carb diet was more helpful for weight loss than a calorie-restricted, low fat diet.

Originally designed to help treat people with epilepsy, the diet works by triggering a metabolic process in the body called “ketosis,” in which ketones are released into the bloodstream.

Basically, this means that without the glucose (aka sugar) we obtain from eating carbs, the body is forced to burn fat for fuel, spurring rapid weight loss.

So, what’s the catch? Keto can be difficult to sustain long term — particularly for vegetarians, who don’t have as many protein sources on which to fill up.

High fat diets can cause gastrointestinal issues in some people. What’s more, we don’t yet understand the long-term health effects of a high fat diet.

5. Don’t forget to water yourself

Researchers found that drinking 16 ounces of water before a meal helped people eat less and ultimately lose a little more weight over the course of 3 months.

But is that just because you eat less when you have a belly full of water? Not necessarily! Short-term experiments from 2008 concluded that drinking water while watching weight increased metabolism.

And a small German study from 2003 also concluded that drinking 2 liters of water per day appears to spur the metabolism.

Proper hydration packs a host of body benefits, improving digestion, circulation, regulation of body temperature, and boosting organ function.

6. Lose liquid sugar

We don’t fill up on 320 calories of soda the same way as, say, 320 calories of lean chicken, veggies, or brown rice. “Empty calories” from sugary beverages have no nutritional value and therefore are no bueno.

Consumption of sugary drinks is largely to blame for rising rates of obesity and diabetes. Studies conclude that the association between sugar-sweetened beverages and weight gain is strong enough to warrant public health warnings.

Orange juice contains a good amount of vitamin C, but if your goal is to lose weight, you might want to drink it sparingly in favor of simply drinking water and eating fruit in its whole form.

7. Get your fill of fiber

If you don’t eat enough fiber, you’re not alone; few Americans do. Americans consume about 16 grams per day — well short of the recommended 25 grams.

One study found that those with obesity tend to consume less fiber than those without obesity. That’s not good, because fiber is important for preventing chronic disease.

A high fiber diet has been shown to be an easy and effective way to help people with extra weight shed some pounds.

High fiber cereals, broccoli, and legumes are good sources to stock in your pantry. Throw a banana on your cereal for some fiber, potassium, and vitamin C (and no fat). Boom! You’re on a more fibrous road already.

Gaining weight can be difficult for some people, and there are many possible reasons that someone might struggle to keep weight on.

Talk to your doctor about working some of these tips into your diet:

  • Space your meals throughout the day. If you tend to feel full faster than other people, eating smaller meals more frequently may help you take in more calories.
  • Blend some smoothies packed with healthy, high calorie ingredients such as nuts, flaxseed, and a nut butter of your choice.
  • Curb drinking liquids before meals, since they might fill you up.
  • Try snacking before bed: Peanut butter and crackers or a whole-wheat sandwich with avocado and tomato are healthy choices.
  • Exercise! Sure, it burns calories, but it also stimulates your appetite and helps you gain muscle.

Healthy weight depends on a bunch of factors, including body type, age, muscle mass, hormones, and water retention.

Your ultimate goal should be to feel healthy and comfortable in your own skin, no matter what the scale says.

Talk to your doctor or a nutritionist about setting healthy, reasonable goals for diet and exercise. But in the meantime, know that a calorie calculator can help you get started and give you some numbers to work with.