Estimate BMR, TDEE, maintenance calories, weight-loss calories, weight-gain calories, and suggested daily macros based on your body stats and activity level.
| Item | Amount |
|---|
Calories are the currency of your body's energy system — and knowing exactly how many you need each day is the most important number in any weight management plan. Too many and you gain weight. Too few and you lose muscle, slow your metabolism, and feel exhausted. The right number — specific to your body, your lifestyle, and your goal — is what this free calorie calculator finds for you in seconds. Whether you want to lose weight, maintain where you are, or build muscle, this tool gives you a real, personalised daily calorie target backed by science.
The US Dietary Guidelines for Americans (updated every five years by the USDA and HHS) suggest 1,600–2,400 calories per day for adult women and 2,000–3,000 for adult men — but these are broad population averages. Your actual need depends on your age, height, weight, sex, and activity level. The only way to get an accurate personal number is to calculate it. According to the US Dietary Guidelines, calorie needs can vary by more than 1,000 calories per day between two people of the same sex and age.
This calorie calculator uses the Mifflin-St Jeor equation — the most accurate BMR formula for non-athletic adults, validated by multiple studies including research published in the American Journal of Clinical Nutrition. It first calculates your Basal Metabolic Rate (BMR) — the calories your body burns at rest — then multiplies by an activity factor to give your Total Daily Energy Expenditure (TDEE). Your daily calorie goal is then set above or below TDEE depending on your goal.
For weight loss: TDEE minus 500 calories/day produces approximately 1 lb of fat loss per week. Minus 750 calories/day produces approximately 1.5 lbs/week. Going below your BMR is generally not recommended without medical supervision.
For muscle gain: TDEE plus 250–500 calories/day (a "lean bulk") with adequate protein intake (0.7–1g per lb of bodyweight) supports muscle growth while minimising fat gain.
For maintenance: eating at TDEE keeps your weight stable over time.
Calorie needs peak in your 20s and early 30s, then gradually decline as muscle mass decreases and activity levels often drop. Here's a practical guide based on moderate activity levels:
Women: Age 19–30 approximately 2,000–2,200 cal/day | Age 31–50 approximately 1,800–2,000 | Age 51+ approximately 1,600–1,800
Men: Age 19–30 approximately 2,400–2,600 cal/day | Age 31–50 approximately 2,200–2,400 | Age 51+ approximately 2,000–2,200
These figures come from the USDA Dietary Reference Intake calculator. Your individual number may be higher or lower depending on body composition and actual activity.
One pound of body fat stores approximately 3,500 calories of energy. To lose one pound per week, you need to create a weekly deficit of 3,500 calories — or 500 calories per day. This is the foundational math behind nearly every evidence-based weight loss program. In practice, the relationship isn't perfectly linear (your body adapts), but it's accurate enough for planning. A 500-calorie daily deficit from diet alone or split between diet and exercise is the safest, most sustainable approach for most healthy adults.
A calorie deficit means consuming fewer calories than your body burns. A moderate deficit of 500 calories/day is widely recommended as the sweet spot — large enough to produce meaningful fat loss (roughly 1 lb/week) but small enough that you preserve muscle, maintain energy levels, and can sustain it without feeling deprived. Deficits larger than 1,000 calories/day often cause muscle loss, metabolic slowdown, nutrient deficiencies, and are very difficult to maintain. The National Institutes of Health weight management guidelines support a slow and steady approach.
For fat loss, your calorie target is below TDEE, protein intake is kept high (to preserve muscle), and resistance training is still recommended to minimise muscle loss during the deficit. For muscle building, your calorie target is above TDEE, you're in a "surplus," and protein intake is even more critical to give muscles the building blocks they need. These two goals require different calorie targets and different macronutrient distributions — which is why using a tool that accounts for your specific goal matters. See our Macro Calculator for a personalised protein, carb, and fat breakdown to go with your calorie target.
Tracking calories works — multiple meta-analyses confirm that self-monitoring food intake is one of the strongest predictors of successful weight management. But it doesn't have to be obsessive or forever. Here's a practical approach:
Use a tracking app (MyFitnessPal, Cronometer, Lose It) for 2–4 weeks to build awareness of what's in your typical meals. After that, most people have a strong enough mental model to estimate portions without constant logging. Weigh food with a kitchen scale at first — portion sizes are notoriously underestimated, especially for calorie-dense foods like nuts, oils, and cheese. The USDA's MyPlate resource offers free guidance on portion sizes and balanced eating.
Knowing where your calories are actually coming from is half the battle. Some common reference points: one large egg ≈ 70 calories | one slice of whole wheat bread ≈ 80 calories | one medium banana ≈ 105 calories | one cup of cooked white rice ≈ 205 calories | one tablespoon of olive oil ≈ 120 calories | one large chicken breast (cooked) ≈ 280 calories | one 20oz regular soda ≈ 250 calories. Liquid calories from sodas, juice, alcohol, and specialty coffee drinks are the single most common cause of unaccounted calorie surpluses in the American diet.
It depends on how you're using the calculator. If you selected an activity level that already accounts for your typical exercise (e.g., "moderately active — exercise 3–5 days/week"), then those exercise calories are already included in your TDEE. Don't add them again. If you selected "sedentary" and then exercise on top of that, you can add back approximately 50%–70% of your estimated exercise calories (not all of them, as fitness trackers tend to overestimate burn). Our Calories Burned Calculator gives activity-specific estimates to help.
Enter your sex, age, height, and weight. Choose metric (kg/cm) or imperial (lbs/inches). Select your typical activity level. Choose your goal — lose weight, maintain, or gain muscle. Click Calculate. You'll see your BMR, your TDEE, and specific daily calorie targets for each goal level. Use these numbers as your starting point, track for 2–3 weeks, and adjust based on actual results. If you're not losing or gaining as expected, adjust by 100–150 calories in the appropriate direction.
BMR Calculator | TDEE Calculator | Macro Calculator | BMI Calculator | Ideal Weight Calculator | Calories Burned Calculator | Protein Calculator | Body Fat Calculator
For most adult women in the US, eating 1,200–1,500 calories per day produces steady weight loss, though the exact number depends on your size and activity level. A better approach: calculate your TDEE with our tool and subtract 500 calories for 1 lb/week loss. Very few women should go below 1,200 calories/day without medical supervision, as this risks nutrient deficiencies and metabolic slowdown.
Most men need to eat 1,500–2,000 calories per day to lose weight at a healthy pace of 1–2 lbs/week, depending on height, weight, and activity. Men generally have higher BMRs than women due to greater muscle mass, so their deficits can be larger while still staying above minimum thresholds. Calculate your personal TDEE and subtract 500–750 calories for your target.
For many people — especially taller, more active, or heavier individuals — 1,200 calories is too low and will likely cause fatigue, muscle loss, nutrient deficiencies, and metabolic adaptation that stalls weight loss. For small, sedentary, older women, 1,200 may be appropriate. The right answer is always relative to your TDEE, not an arbitrary number. If 1,200 is significantly below your BMR, it's too low.
Consistently eating below your BMR deprives your body of the energy it needs for basic organ function. In response, your body can reduce muscle mass (to decrease energy needs), slow thyroid function, lower body temperature, and reduce non-essential activity to compensate — collectively called metabolic adaptation. This makes future weight loss harder, not easier. A moderate deficit above BMR is always the better long-term strategy.
This calorie calculator provides estimates based on established formulas and is for informational purposes only. It is not a substitute for personalised medical or nutritional advice. If you have diabetes, heart disease, an eating disorder history, or any other health condition that affects nutrition, consult your physician or a registered dietitian before changing your calorie intake. For professional nutrition support, visit eatright.org.
The calorie calculator uses the Mifflin-St Jeor equation, the most accurate BMR formula for the general population. Men: 10×weight(kg) + 6.25×height(cm) − 5×age + 5. Women: same minus 161 at the end. That figure is BMR; multiply by an activity factor (1.2 sedentary to 1.9 very active) to get TDEE — your daily calorie maintenance level.
To lose 1 lb per week, eat 500 calories less than your TDEE daily (1 lb of fat = roughly 3,500 calories). For a 180 lb man with a 2,500 TDEE, that is 2,000 calories/day. Aggressive cuts (1,000 deficit) aren't sustainable for most people and trigger rebound weight gain. A moderate 300–500 deficit produces 0.5–1 lb/week loss and is much easier to maintain.
Maintenance calories are simply your TDEE — the calorie intake at which weight remains stable. For a 30-year-old, 5'10", 180 lb moderately active man, that is about 2,700 calories/day. Our calorie calculator produces a maintenance figure plus clear weight-loss and muscle-gain targets (typically maintenance ±500 calories).
Women typically have lower BMRs than men due to lower muscle mass. A 30-year-old, 5'5", 140 lb moderately active woman has a TDEE of about 2,000 calories/day. The Mifflin-St Jeor formula accounts for this accurately. Pregnancy and breastfeeding add 300–500 calories/day to TDEE — use a dedicated pregnancy nutrition calculator for those life stages.
A standard macro split is 30% protein, 40% carbs, 30% fat. On a 2,000-calorie diet: 150g protein, 200g carbs, 67g fat. For muscle gain, shift to 30/50/20. For keto, flip to 25/5/70. Our calculator shows all three splits plus a custom mode. Protein intake of 0.7–1g per pound of body weight is the typical target for anyone exercising.
Your TDEE for maintenance, TDEE minus 300–500 for weight loss, or TDEE plus 300–500 for muscle gain.
Eating fewer calories than your body uses. A 500/day deficit produces roughly 1 lb/week of weight loss.
For most adult women, yes — long-term intake below BMR (typically 1,300–1,500) triggers metabolic slowdown and rebound weight.
Within 5–10% for most adults. Individuals with unusually high muscle mass or medical conditions may need clinical testing.
Protein first (preserves muscle during deficit), then control overall calories. A common split is 30% protein, 40% carbs, 30% fat.