Weight Loss Calculator

Daily Calorie Needs

Not sure how many calories you should eat to lose weight? The Australian Dietary Guidelines recommend choosing the right amount of nutritious foods and drinks to match your energy needs and maintain a healthy weight. These needs vary based on your age, sex, body size, and activity level. Women usually need 1,600 to 2,400 calories a day, while men need 2,000 to 3,000 — but those numbers are for maintaining weight, not losing it. If you’re struggling to figure out how many calories to eat, using a calorie calculator to identify how many calories to loose weight is a great start.

Your body uses energy every day just to stay alive. This is known as your basal metabolic rate (BMR) — the amount of energy needed for basic functions like breathing, pumping blood, and keeping organs running, even when you’re completely at rest.

On top of your BMR, your total energy needs are influenced by factors like age, sex, weight, height, activity level, and whether you’re pregnant or breastfeeding.

To maintain your weight, your daily energy intake should match what your body uses. To lose weight, you need to create an energy deficit — usually by eating less, moving more, or both. The old idea that cutting 3,500 calories equals 1 pound of weight loss doesn’t hold true for everyone. Weight loss depends on many variables and tends to slow over time.

If you’re calculating your daily energy needs, consider these factors.

Current Weight

Start by weighing yourself to identify your current weight. This number helps estimate how many calories your body needs each day to stay the same or begin losing weight. If your weight is in a healthy range for your height, aim to maintain it by meeting your daily energy needs. Tools like BMI charts can help give you a general guide, though “healthy weight” varies by individual.

If you’re working toward weight loss, calorie calculators can estimate the number of calories you need to eat to lose weight steadily.

Goal Weight

Choose a goal weight that feels achievable. You can test different targets in most calculators to compare your daily calorie goals for each scenario.

Goal Date

Many calculators ask for a target date. A shorter timeline means a lower daily calorie goal. A longer one usually offers more flexibility. Be careful — entering a large weight loss goal with a tight timeline can result in a calorie target that’s too low to sustain safely.

Most experts advise staying above 1,200–1,300 calories for women and 1,400–1,500 for men unless under medical supervision.

Birth Sex

Calorie needs differ by biological sex due to differences in body size and muscle mass. Men often require more energy than women.

Age

Younger people usually need more calories than older adults. As you age, you tend to lose muscle and become less active, which lowers your calorie needs.

Height

Taller bodies need more energy for basic functions and physical activity.

Activity Level

Activity level affects how many calories you burn. Categories include:

• Sedentary: only basic movement

• Moderately active: walking 1.5–3 miles daily

• Active: walking more than 3 miles daily

• Highly active: intense exercise most days or a labor-intensive job

Set Realistic Goals

Set goals that are practical and within reach. Sudden, extreme changes to your habits rarely lead to long-term weight loss, but consistent and steady effort often does. The CDC suggests that losing 1 to 2 pounds per week makes it more likely that the weight will stay off.

Rather than aiming for a random number, try focusing on losing 5 to 10% of your body weight over a few months. This approach is manageable and backed by both research and real-world success.

Data from over 16,000 Lose It! users found that slower plans, like targeting half a pound per week, were more successful. Those who reached their goals typically took about six months.

Even modest weight loss can offer health improvements. Participants in the CDC’s National Diabetes Prevention Program who lost 5 to 7% of their starting weight and exercised 150 minutes per week cut their risk of type 2 diabetes by 58%.

Every healthy step counts. If you’re eating more vegetables or moving more, you’re supporting your health — even if the scale doesn’t move right away.

Diet & Weight Loss

Your diet plays a major role in weight loss. It’s important to meet your daily energy needs while also getting enough nutrients to support your health. A balanced eating plan should be part of any approach, whether or not weight loss is the goal.

A nutritious diet includes:

• Carbohydrates, proteins, and healthy fats

• Vegetables and fruits

• Whole grains

• Lean protein sources like chicken, tofu, or fish

• Healthy fats such as nuts, seeds, olive oil, and avocado

• Low-fat dairy or plant-based alternatives like almond or oat milk[6]

Practical Tips from Dietitians

1. Cut out empty calories from sugary drinks, processed snacks, sweets, and alcohol.

2. Prioritize whole foods with higher nutrient density.

3. Include protein, healthy fats, veggies or fruit, and whole grains in your meals.

4. Choose snacks like raw veggies, fruit with nut butter, or hummus with carrot sticks.

5. Eat meals that are low in calories but high in volume, like broth-based soups or salads with dark leafy greens.

These habits support weight loss while also helping you stay full and nourished.

Exercise & Weight Loss

Exercise offers wide-ranging benefits beyond weight loss. It helps lower the risk of chronic diseases like heart disease and diabetes, improves bone and muscle strength, supports brain function as you age, and reduces symptoms of anxiety and depression.

Data from over 16,000 Lose It! users found that those who exercised at least once a week were nearly twice as likely to hit their weight loss goals compared to those who didn’t. Still, weight loss from exercise alone is often limited unless combined with dietary changes.

While more than 150 minutes of aerobic activity per week can support modest weight loss (2–3 kg), research shows people often eat more when they exercise due to increased hunger and hormonal shifts.

How to Add Movement to Your Day

• Walk during lunch breaks

• Replace social catchups with walks or fitness classes

• Schedule short workouts during the week

Why Self-Monitoring Matters

Tracking habits improves weight loss results. Logging food, activity, and weight—even a few days a week—can improve outcomes. Celebrate non-scale progress too: better sleep, more strength, or improved stamina.

Common Challenges

Weight loss isn’t always a smooth process. Many people face hurdles like emotional eating, plateaus, or waning motivation.

Emotional Eating

Emotional eating often stems from unmanaged stress. Instead of reaching for food, try pausing and taking a few deep breaths. Talk to a friend or, if needed, seek support from a mental health professional.

Plateaus

If your progress stalls, review your habits. Look back at your food or activity logs to see if portion sizes have crept up or workouts have become less consistent. Adjust your routine slightly — reducing your calorie intake by 100 to 200 calories or increasing your physical activity might help.

Staying Motivated

Reconnect with your reason for starting. Write it down or place a reminder somewhere visible. When progress feels slow, remember that consistency is more powerful than perfection.

Getting Started

Use a weight loss calculator to estimate your daily calorie needs. Pair it with a nutritious eating plan and regular movement. If you need help setting realistic goals, a registered dietitian or healthcare provider can guide you.