Introduction
This weight loss calorie calculator shows you how many calories to eat each day to reach your goal weight by your target date. It uses your age, sex, height, weight, and activity level to find how many calories your body burns. Then it builds a plan that puts you in a safe calorie deficit so you lose weight at a steady pace.
Unlike simple calculators that use a flat "3,500 calories per pound" rule, this tool uses an adaptive body weight model. That means it accounts for how your metabolism slows down as you lose weight, giving you a more accurate and realistic plan. It also sets a calorie floor of 1,500 kcal per day for men and 1,200 kcal per day for women, so your intake never drops too low.
Along with your daily calorie target, you get a full macronutrient breakdown, a suggested meal split, two zigzag calorie schedules to prevent plateaus, and a projected weight loss chart. Enter your details below and press Calculate to get your personalized plan.
How to Use Our Weight Loss Calorie Calculator
Enter your body stats, goal weight, and timeline below. The calculator will tell you how many calories to eat each day to reach your goal, plus a meal plan, macro targets, and a weight loss chart.
Unit System: Pick US/Imperial or Metric at the top. This changes all weight and height fields to match your preferred units.
Age: Enter your current age in years. This must be between 15 and 80. Your age affects how many calories your body burns at rest. The Mifflin-St Jeor equation was derived on adults aged 19 to 78, so younger ages extrapolate.1
Sex: Select Male or Female. This changes your base calorie burn and sets the safe minimum calorie floor for your plan.
Height: Enter your height in feet and inches, or in centimeters if you chose Metric. Your height helps calculate how many calories your body needs each day.
Current Weight: Enter how much you weigh right now in pounds or kilograms.
Goal Weight: Enter the weight you want to reach. This must be different from your current weight.
Start Date: Pick the date you plan to begin your weight loss journey.
Target Date: Pick the date you want to reach your goal weight by. This must be after your start date. If your timeline is too short and would drop calories below a safe level, the calculator will extend it for you.
Activity Level: Choose the option that best fits your typical week. This ranges from sedentary (no exercise) to extra active (hard training twice a day). A higher activity level means your body burns more calories.
BMR Formula (Advanced): Click "Advanced Settings" to pick a different formula for your base calorie burn. Mifflin-St Jeor works best for most people. Choose Katch-McArdle only if you know your body fat percentage.
Body Fat Percentage (Advanced): This field appears only when you select the Katch-McArdle formula. Enter your body fat percentage between 1 and 70.
Display Results In (Advanced): Choose whether to show your results in calories (kcal) or kilojoules (kJ).
When you are ready, press the Calculate button to see your results. Press Reset at any time to clear your entries and start over.
How This Weight Loss Calorie Calculator Works
This calculator figures out how many calories you need to eat each day to reach your goal weight by your target date. It uses your age, height, current weight, sex, and activity level to find your Total Daily Energy Expenditure (TDEE), the number of calories your body burns in a normal day. Then it calculates how much less you need to eat to lose weight at a steady pace.
What Is a Calorie Deficit?
A calorie deficit means eating fewer calories than your body uses. When you do this, your body turns to stored fat for energy, and you lose weight. The bigger the deficit, the faster you lose weight, but going too low can be unsafe. This calculator never drops below 1,500 calories per day for men or 1,200 calories per day for women. The National Heart, Lung, and Blood Institute's guide describes supervised low-calorie diets of 1,000 to 1,200 calories per day for most women and 1,200 to 1,600 for men.8
Your BMR and Why It Matters
Your Basal Metabolic Rate (BMR) is the number of calories your body needs just to stay alive: breathing, pumping blood, and keeping your organs running. Even if you stayed in bed all day, your body would still burn this amount. The calculator multiplies your BMR by an activity factor to estimate your true daily burn. You can choose from three BMR formulas. Mifflin-St Jeor was derived in 1990 from 498 healthy adults aged 19 to 78,1 and a systematic review found it the most reliable of the common equations.6 Harris-Benedict is the 1918 original2 as re-fitted by Roza and Shizgal in 1984,3 with the coefficients as printed in a 2021 systematic review.4 Katch-McArdle is for people who know their body fat percentage; its published form is Cunningham's 1991 equation, 370 + 21.6 × lean body mass in kilograms.5
Dynamic Weight Projection
Most simple calculators treat weight loss as a straight line. This one does not. It uses a model based on research by Dr. Kevin Hall at the National Institutes of Health, whose analysis of the 3,500-calorie rule showed that the energy content of lost weight depends on body composition.7 As you lose weight, your body burns fewer calories. This calculator accounts for that change week by week, giving you a more realistic timeline and a more accurate daily calorie target.
Zigzag Calorie Cycling
The calculator also gives you two zigzag schedules. Instead of eating the same amount every day, you eat more on some days and less on others. The weekly total stays the same, so you still lose weight at the same rate. Many people find this easier to stick with because it allows for bigger meals on certain days.
Macronutrient Breakdown
Calories are not the whole story. The calculator splits your daily intake into carbs, protein, and fat across four common diet styles: balanced, low-fat, low-carb, and high-protein. Protein helps you keep muscle while you lose fat. Picking the right balance can make your diet feel more satisfying and easier to follow.
Tips for Safe Weight Loss
- Aim to lose no more than 1 to 2 pounds per week, the rate the National Heart, Lung, and Blood Institute's guide recommends.8 That is about 0.5 to 1 kg a week.
- Never eat below the safe calorie floor without a doctor's guidance.
- Drink plenty of water, get enough sleep, and include some physical activity.
- Track your BMI and waist-to-hip ratio alongside the scale to get a fuller picture of your progress.
- Use this calculator as a starting point, not a medical plan. Talk to a healthcare provider before making big changes to your diet.