How to lose 40 lbs in a month

To lose 40 lbs in a month, a typical 30-year-old male (5'9", 176.4 lbs, sedentary) burning about 2099 calories per day would need to eat approximately 800 calories per day.

Note for men: This goal may be too aggressive for healthy weight loss. A safe rate of loss for men is typically 0.5-1 kg (1-2 lbs) per week.

A typical 30-year-old female (5'3", 132.3 lbs, sedentary) burning about 1547 calories per day, would need to eat approximately 800 calories per day.

Note for women: This goal may be too aggressive for healthy weight loss. A safe rate of loss for women is typically 0.5-0.75 kg (1-1.5 lbs) per week.

These are rough estimates. Your actual calorie needs depend on your age, gender, height, weight, and activity level. Use the calculator below to get a personalized estimate.

Enter your parameters below to get a personalized estimate

Adjust the parameters below to see projections based on your own body metrics.

Your Parameters
ft
in
Daily Energy Expenditure (TDEE)

Estimated from your parameters

2099 kcal/day

Your Goal

To lose 40 lbs in 1 month, you would need to eat approximately 0 calories per day, given your TDEE of 2099 kcal/day. After reaching your goal, your maintenance intake would be approximately 1881 kcal/day.

Warning: Eating below 1,200 kcal/day is generally not recommended without medical supervision. Consider a longer timeframe — at 1,200 kcal/day it would take approximately 2.4 months.

Estimated Weight Over Time
Daily Calories1 Week2 Weeks1 Month3 Months
0 kcalYour goal (-100%)172.2 lbs168 lbs158.7 lbs125.9 lbs
1679 kcal-20%175.5 lbs174.6 lbs172.8 lbs166.2 lbs
1889 kcal-10%175.9 lbs175.5 lbs174.6 lbs171.3 lbs
2099 kcalMaintenance176.4 lbs176.4 lbs176.4 lbs176.4 lbs
2308 kcal+10%176.8 lbs177.3 lbs178.1 lbs181.4 lbs
2518 kcal+20%177.3 lbs178.1 lbs179.9 lbs186.5 lbs
Weight Projection
0 kcal (Your goal (-100%))
1679 kcal (-20%)
1889 kcal (-10%)
2099 kcal (Maintenance)
2308 kcal (+10%)
2518 kcal (+20%)
Target

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