How Many Calories to Lose 1 Pound Per Week

To lose 1 pound per week, you need to create a calorie deficit of 500 calories per day. Since one pound of body fat contains approximately 3,500 calories, a daily deficit of 500 calories produces a 3,500-calorie weekly deficit — enough to lose roughly one pound over seven days.

The 500-calorie-per-day rule is a starting point, not a universal guarantee. Individual results vary based on starting weight, body composition, hormone levels, and metabolic adaptation. According to the National Institutes of Health (NIH), the 3,500-calorie-per-pound estimate holds reasonably well for most adults as a planning tool, even though actual fat loss involves more complex physiology. What matters for practical purposes is finding your specific daily calorie target — which requires knowing your TDEE (Total Daily Energy Expenditure).

Use the free Calorie Calculator at RoughTools to calculate your personal daily calorie target instantly — or follow the step-by-step method below.

The Calorie Deficit Formula for Losing 1 Pound Per Week

The calculation has two parts: first find your maintenance calories (TDEE), then subtract 500.

Step 1 — Calculate BMR using the Mifflin-St Jeor equation:

For women:

BMR = (10 × weight in kg) + (6.25 × height in cm) - (5 × age) - 161

For men:

BMR = (10 × weight in kg) + (6.25 × height in cm) - (5 × age) + 5

Step 2 — Multiply by your activity factor to get TDEE:

TDEE = BMR × Activity multiplier

Step 3 — Subtract 500 for 1 pound per week loss:

Daily calorie target = TDEE - 500

Where:

BMR (Basal Metabolic Rate) — the calories your body burns at complete rest, just to maintain organ function
TDEE — your total daily calorie burn including all physical activity
Activity multiplier — a factor from 1.2 (sedentary) to 1.9 (extremely active)

Worked example: 34-year-old woman, 172 lbs, 5'6", moderately active

Step 1 — Convert units and calculate BMR:

Weight: 172 lbs ÷ 2.205 = 78.0 kg
Height: 5'6" = 66 inches × 2.54 = 167.6 cm
Age: 34

BMR = (10 × 78.0) + (6.25 × 167.6) - (5 × 34) - 161
BMR = 780 + 1,047.5 - 170 - 161
BMR = 1,496.5 calories/day

Step 2 — Multiply by activity factor (moderately active = 1.55):

TDEE = 1,496.5 × 1.55 = 2,319.6 ≈ 2,320 calories/day

Step 3 — Subtract 500 for 1 lb/week loss:

Daily target = 2,320 - 500 = 1,820 calories/day

The result: this person needs to eat 1,820 calories per day to lose approximately 1 pound per week. At this intake, her weekly calorie deficit totals 3,500 calories — the energy equivalent of one pound of body fat.

The Mifflin-St Jeor equation is the formula most widely validated for accuracy among modern BMR calculators, as established in a 2005 review published in the Journal of the American Dietetic Association.

How to Calculate Your Daily Calorie Target Step by Step

Gather your four inputs. You need your current weight (in pounds or kilograms), height (in inches or centimeters), age in years, and an honest assessment of your daily activity level. Use your weight as it is today, not a goal weight — BMR is based on your current body mass, which changes as you lose weight.
Calculate your BMR using the Mifflin-St Jeor formula. Convert pounds to kilograms (divide by 2.205) and inches to centimeters (multiply by 2.54). Apply the formula for your sex. A 38-year-old man weighing 198 lbs (89.8 kg) and 5'11" (180.3 cm) has a BMR of approximately (10 × 89.8) + (6.25 × 180.3) - (5 × 38) + 5 = 898 + 1,127 - 190 + 5 = 1,840 calories.
Select your activity multiplier honestly. Most people overestimate their activity level, which inflates TDEE and causes confusion when the diet does not produce expected results. The multipliers are: sedentary (desk job, no exercise) = 1.2; lightly active (exercise 1–3 days/week) = 1.375; moderately active (exercise 3–5 days/week) = 1.55; very active (exercise 6–7 days/week) = 1.725. When in doubt, use the lower multiplier.
Multiply BMR by your activity factor to get TDEE. This is your maintenance number — the calories needed to stay at your current weight. The 38-year-old man at 1.55 activity: TDEE = 1,840 × 1.55 = 2,852 calories/day. Eating exactly this amount would maintain his weight indefinitely.
Subtract 500 calories for a 1 lb/week loss target. 2,852 - 500 = 2,352 calories/day. This is his specific daily calorie target. Eating this amount every day, without increasing or decreasing activity, should produce roughly 1 pound per week of fat loss.
Verify the result is above 1,200 calories (women) or 1,500 calories (men). These are the general minimum thresholds below which nutrient deficiencies become a serious risk. If subtracting 500 from your TDEE puts you below these minimums, reduce the deficit — target 250 calories below TDEE instead and accept a slower 0.5 lb/week rate. Use the free calorie calculator to confirm the result is within a safe range.

Pro tip: Recalculate your TDEE and daily target every 10–15 pounds of weight loss. As you weigh less, your BMR decreases — which means the same calorie intake produces a smaller deficit over time. Failing to adjust is why weight loss often stalls unexpectedly after the first several weeks.

What Is a Safe Calorie Deficit for Weight Loss?

A safe calorie deficit for most adults is 250–750 calories per day below TDEE, producing weight loss of 0.5–1.5 pounds per week. A deficit larger than 1,000 calories per day (targeting 2+ pounds/week) is generally not recommended for most people without medical supervision.

Here is why the upper limit matters:

| Daily deficit | Weekly loss | Risk level | |---|---|---| | 250 calories | ~0.5 lb | Low — sustainable long-term | | 500 calories | ~1 lb | Low to moderate — standard recommendation | | 750 calories | ~1.5 lbs | Moderate — manageable for most, hunger increases | | 1,000 calories | ~2 lbs | Higher — muscle loss risk rises, metabolism may slow | | 1,200+ calories | ~2.5+ lbs | High — not recommended without medical supervision |

The risk of large deficits is not just hunger — it is muscle loss. When calorie intake drops too low, the body supplements its energy needs by breaking down muscle tissue alongside fat. A 2008 study in the American Journal of Clinical Nutrition found that higher-protein diets (1.2–1.6g per kg of body weight) significantly reduce muscle loss during caloric restriction. The deficit size matters; protein intake matters more.

A 500-calorie daily deficit from food is generally more sustainable than a 750-calorie deficit achieved entirely through exercise, because the exercise deficit is harder to maintain consistently and exercise often increases appetite.

What Is TDEE and How Is It Different from BMR?

BMR (Basal Metabolic Rate) is the calories your body needs at complete rest — lying still, not digesting food, just keeping your heart beating, lungs breathing, and organs functioning. It represents roughly 60–70% of total daily calorie burn for most people.

TDEE (Total Daily Energy Expenditure) is your complete daily calorie burn: BMR plus all the energy used for digestion, daily movement, and intentional exercise. TDEE is always higher than BMR — often 20–90% higher depending on activity level.

This distinction matters enormously for calorie targets:

| Metric | 34-year-old woman example | Use case | |---|---|---| | BMR | 1,497 calories | Absolute minimum — do not eat below this | | TDEE (sedentary) | 1,796 calories | Target if you sit all day and never exercise | | TDEE (moderate) | 2,320 calories | Target if you exercise 3–5 days/week | | TDEE (very active) | 2,582 calories | Target if you exercise intensely 6–7 days/week | | 1 lb/week deficit (moderate) | 1,820 calories | Subtract 500 from TDEE |

Using BMR as your food target — a common mistake — essentially gives you the calories needed to lie in a hospital bed. On a real day with walking, digestion, and any movement, your body burns far more than BMR. The TDEE is the correct baseline for any weight loss calculation.

What Happens If You Eat Too Few Calories While Trying to Lose Weight?

Eating too few calories — typically defined as more than 1,000 calories below TDEE — triggers physiological responses that work against fat loss rather than accelerating it.

The three main consequences:

Metabolic adaptation. The body responds to severe restriction by reducing non-exercise activity (unconscious movement like fidgeting) and lowering the metabolic rate. Research in Obesity journal found that contestants on extreme weight loss programs experienced metabolic rates 15–25% lower than expected for their body size — a "metabolic slowdown" that persisted years after the diet ended.

Muscle tissue breakdown. Without adequate calories and protein, the body breaks down muscle for energy. Less muscle means lower BMR — creating a cycle where the body needs fewer calories to maintain weight, making future weight loss harder.

Nutritional deficiencies. Eating below roughly 1,200 calories (women) or 1,500 calories (men) makes it extremely difficult to meet minimum requirements for protein, vitamins, and minerals through food alone, even with careful food choices.

The practical takeaway: a moderate, sustainable deficit of 250–500 calories produces slower but better-quality weight loss than an aggressive deficit. Eating 1,820 calories consistently for 52 weeks produces better outcomes than eating 1,200 calories for 8 weeks, rebounding, and repeating.

Common Mistakes to Avoid When Calculating Calories to Lose Weight

Using goal weight instead of current weight to calculate BMR. BMR is based on how much metabolic tissue you currently have. A 190-pound person has a higher BMR than a 150-pound person — using goal weight underestimates maintenance calories and creates a deficit larger than intended, which accelerates muscle loss.
Overestimating activity level. Selecting "very active" when your actual exercise is two gym sessions per week inflates TDEE by 300–400 calories. This creates a situation where you eat your calculated "deficit" calories but actually maintain weight. When in doubt, pick the activity level below your initial guess.
Not tracking calorie intake accurately. Research consistently shows people underestimate their calorie intake by 20–40%. Common culprits: cooking oils not measured, condiments not counted, portion sizes eyeballed. Accurate food tracking for even two weeks dramatically improves awareness of where calories actually come from.
Expecting the same deficit to produce the same loss indefinitely. As weight decreases, BMR decreases. The 500-calorie deficit calculated at 172 pounds produces a smaller deficit at 155 pounds — because TDEE at 155 pounds is lower. Recalculate every 10–15 pounds of loss to keep the deficit calibrated.
Confusing calories burned from exercise with a blank check to eat more. A 45-minute run burns roughly 300–450 calories for most people. Adding this back to the daily food budget eliminates the deficit. Exercise calories contribute to weight loss only when not fully offset by eating — which most tracking apps incorrectly encourage by adding exercise calories to your daily "budget."

Frequently Asked Questions

How many calories should I eat per day to lose weight? Your daily calorie target depends on your TDEE minus your chosen deficit. For most adults, eating 1,500–2,000 calories per day produces gradual weight loss. On the example above, 1,820 calories/day produces approximately 1 pound per week of fat loss for a moderately active 34-year-old woman at 172 pounds. Your specific number will differ — use the calorie calculator to find your personal target.

What if I want to lose weight faster than 1 pound per week? Targeting 1.5 pounds per week requires a 750-calorie daily deficit; 2 pounds per week requires 1,000 calories below TDEE. Both are achievable without medical supervision for people with significant weight to lose (30+ pounds overweight) but become harder to maintain and riskier as you approach a healthy weight. Prioritize protein intake (at least 0.7g per pound of body weight) to minimize muscle loss at larger deficits.

What is the difference between a calorie deficit and intermittent fasting? A calorie deficit is about how much you eat; intermittent fasting is about when you eat. Intermittent fasting (16:8, 5:2, etc.) produces weight loss primarily by creating a calorie deficit — by shrinking the eating window, most people naturally consume fewer calories. Research does not show intermittent fasting produces faster fat loss than an equivalent calorie deficit over the same period when total calories are matched. Choose the approach that makes the deficit easiest to maintain consistently.

How many calories do I burn per day without exercising? Without intentional exercise, most adults burn between 1,600 and 2,400 calories per day through BMR plus basic daily movement. A sedentary 35-year-old woman at 165 pounds burns approximately 1,750–1,800 calories on a typical desk-work day. A sedentary 35-year-old man at 195 pounds burns approximately 2,100–2,200 calories. The BMR calculator gives you a precise number for your body.

When should I recalculate my daily calorie target? Recalculate every 10–15 pounds of weight change, after a significant change in activity level, or if weight loss has stalled for more than 3–4 consecutive weeks despite adherence. As you lose weight, your BMR decreases — the calorie target that created a deficit at 185 pounds may only maintain weight at 165 pounds. Adjusting keeps the deficit calibrated to your current body.

These calculations are estimates based on population-average formulas. Individual metabolic rates vary. Consult your doctor before making significant changes to your diet, especially if you have any medical conditions or take medications.

Use the Free Calorie Calculator

The Free Calorie Calculator at RoughTools calculates your BMR and TDEE using the Mifflin-St Jeor equation, then instantly shows your daily calorie target for any weight loss rate — 0.5, 1, or 1.5 pounds per week. It also breaks down the minimum safe calorie floor for your body and flags if your target falls below recommended thresholds. No account needed, no data stored, completely free.

Free Calorie Calculator →

You might also need:

BMI Calculator — calculate your body mass index to contextualize your weight goal
Body Fat Calculator — estimate body fat percentage to set a body composition goal
Macronutrient Calculator — split your daily calories into protein, carbs, and fat targets
BMR Calculator — calculate your basal metabolic rate alone without the full TDEE