Make informed health decisions with our free, easy-to-use calculators for nutrition, fitness, body metrics, and more.
Calculate your Body Mass Index (BMI) to assess your weight relative to height.
Estimate your body fat percentage using various methods.
Calculate your ideal weight range based on height, gender, and frame size.
Calculate your waist-to-hip ratio to assess health risks.
Calculate daily calorie needs based on activity level and goals.
Calculate your ideal macronutrient breakdown for your diet goals.
Create balanced meal plans based on your calorie and macro targets.
Calculate your recommended daily water intake based on weight and activity.
Calculate calories burned during different types of exercise.
Calculate your target heart rate zones for optimal training.
Estimate your one-repetition maximum lift for weight training.
Calculate running or walking pace, time, and distance for training.
Calculate your Basal Metabolic Rate (BMR) — the calories your body needs at rest.
Calculate due date, conception date, and important pregnancy milestones.
Estimate blood alcohol content (BAC) based on drinks consumed.
Determine your body shape type based on measurements.
Plan weight loss goals and track progress over time.
Calculate calorie deficit needed to lose weight at a specific rate.
Calculate the calories needed to maintain your current weight.
Find your healthy weight range based on height, age, and body frame.
BMI (Body Mass Index) is a measure of body fat based on height and weight. It's calculated using the formula: BMI = weight(kg) / height²(m²). For imperial units: BMI = 703 × weight(lb) / height²(in²). BMI categories are: Underweight (below 18.5), Normal weight (18.5-24.9), Overweight (25-29.9), and Obese (30 and above). While BMI is useful for population studies, it doesn't account for muscle mass, bone density, or body composition.
To lose weight, you need to create a calorie deficit by consuming fewer calories than you burn. A safe and sustainable weight loss rate is 1-2 pounds per week, which requires a deficit of 500-1000 calories per day. Your exact calorie needs depend on your age, gender, weight, height, activity level, and metabolic health. Our Calorie Calculator can help determine your specific needs based on your weight loss goals.
BMR (Basal Metabolic Rate) is the number of calories your body needs to maintain basic physiological functions while at rest. This includes breathing, circulating blood, and cell production. TDEE (Total Daily Energy Expenditure) includes your BMR plus additional calories needed for daily activities, exercise, and digesting food. Your TDEE represents the total calories you burn in a day and is used to determine how many calories you should consume based on your goals.
Macronutrients (proteins, carbohydrates, and fats) should be tailored to your specific goals. General guidelines suggest: Protein: 0.8-2.2g per kg of body weight, depending on activity level and goals. Carbohydrates: 3-10g per kg of body weight, with higher amounts for more active individuals. Fats: 0.5-1.5g per kg of body weight, never going below 15% of total calories. The Macro Calculator can provide personalized recommendations based on your specific needs, activity level, and goals.
Water needs vary by individual, but a common recommendation is the "8×8 rule" (eight 8-ounce glasses daily, about 2 liters). The National Academies of Sciences suggests about 3.7 liters (125 ounces) for men and 2.7 liters (91 ounces) for women, including water from all beverages and foods. Water needs increase with exercise, hot weather, illness, pregnancy, and breastfeeding. A good indicator of proper hydration is light yellow urine.
Heart rate training zones are ranges of heart rate expressed as percentages of your maximum heart rate. They're used to guide exercise intensity for optimal results. Typically, there are five zones: Zone 1 (50-60%): Very light, warm-up/recovery. Zone 2 (60-70%): Light, improves basic endurance and fat burning. Zone 3 (70-80%): Moderate, improves aerobic fitness. Zone 4 (80-90%): Hard, improves anaerobic performance. Zone 5 (90-100%): Maximum, increases maximum performance and speed. Our Heart Rate Zone Calculator can determine your personalized zones.
Body fat percentage can be calculated using several methods: Skinfold measurements using calipers at specific body sites. Bioelectrical impedance analysis (BIA) used in body fat scales. Underwater weighing (hydrostatic weighing). DEXA (Dual-Energy X-ray Absorptiometry) scans. Navy method using neck, waist, and hip measurements (for women) or neck and waist (for men). Each method has different accuracy levels, with DEXA being considered the gold standard. Our Body Fat Calculator uses the Navy method, which provides reasonably accurate estimates for most people.
Calorie burn varies widely depending on the exercise type, intensity, duration, and your body weight. For a 155-pound person, approximate hourly calorie burns are: Walking (moderate pace): 280-350 calories. Running (6 mph): 700-850 calories. Cycling (moderate pace): 450-600 calories. Swimming (moderate pace): 400-500 calories. Weight lifting: 200-400 calories. HIIT workouts: 600-900 calories. Our Exercise Calorie Burn Calculator provides more precise estimates based on your specific weight and activity.
The best way to track fitness progress is to use multiple metrics rather than focusing solely on weight. Consider measuring: Body measurements (waist, hips, chest, arms, thighs). Body composition (body fat percentage, muscle mass). Performance metrics (weights lifted, running times, endurance levels). Progress photos. Subjective factors (energy levels, sleep quality, mood). Regular reassessment using our calculators can help you objectively track these changes over time. Tracking multiple metrics provides a more complete picture of your progress and can be more motivating than relying on scale weight alone.
A healthy and sustainable rate of weight loss is generally 1-2 pounds (0.5-1 kg) per week. This moderate approach helps preserve muscle mass and is more likely to result in lasting weight management. Faster weight loss is possible but often leads to greater muscle loss and may be harder to maintain long-term. Very rapid weight loss can also increase the risk of gallstones, nutritional deficiencies, and other health problems. Individual factors such as starting weight, age, and health status can affect what rate is optimal for you.