Diet Planner — Calorie Deficit & Weight Loss Plan Simulator
Set your target weight and daily calorie goals to automatically calculate weekly loss rate, weeks to goal, and milestone checkpoints. Science-based diet planner using the 7,700 kcal/kg formula.
Daily Deficit
-500 kcal
Weekly Change
-0.45 kg/wk
Time to Goal
18 weeks
Weight Projection
Milestones
5% done
79.6 kg · 1 wks
10% done
79.2 kg · 2 wks
25% done
78 kg · 5 wks
Halfway!
76 kg · 9 wks
75% done
74 kg · 14 wks
Goal!
72 kg · 18 wks
Note: 1 kg of body fat ≈ 7,700 kcal. Results are estimates. Consult a healthcare professional before starting a diet.
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Frequently Asked Questions
Q. Is the 7,700 kcal = 1 kg formula accurate?
It's a well-established approximation based on the energy density of body fat. Actual rate varies by individual metabolism and water retention. Use it as a reference guideline.
Q. How big should my daily calorie deficit be?
A deficit of 500–1,000 kcal/day is generally safe, equating to 0.5–1 kg/week of fat loss. A larger deficit risks muscle loss and metabolic adaptation.
Q. How do I choose my activity level?
Sedentary = 1.2×, light exercise (1–3×/week) = 1.375×, moderate (3–5×/week) = 1.55×, very active (6–7×/week) = 1.725×. This multiplier is applied to your BMR to estimate TDEE.
Q. What should I do after reaching my goal weight?
Transition to maintenance calories (TDEE without deficit). Increase intake gradually to avoid rebound weight gain.
Q. Why is protein intake important during a diet?
Adequate protein (1.2–2g per kg of body weight) during a calorie deficit helps preserve lean muscle mass, keeping your metabolism healthier.
Q. What should I do when I hit a plateau?
As you lose weight, your BMR decreases, slowing progress. Try increasing exercise intensity or slightly adjusting your target calories.
How to Use
Input your current and goal body weight in kg.
Enter your current daily calorie intake and your target intake.
Choose your typical exercise frequency from the activity level options.
See weekly loss rate, estimated weeks to goal, and milestone chart.
Expert Knowledge: Diet Planner — Calorie Deficit & Weight Loss Plan Simulator
The core principle of weight loss is energy balance: when calorie intake < calorie expenditure, body weight decreases. 1 kg of fat ≈ 7,700 kcal, accounting for the energy density of fat tissue (which also contains water and protein). However, the body adapts through Adaptive Thermogenesis — prolonged calorie restriction can reduce basal metabolic rate by 10–25%, making the same deficit progressively less effective. This "metabolic adaptation" is the primary cause of diet plateaus. Periodic Diet Breaks (1–2 week maintenance phases) or Refeeds (temporary calorie increase) can help mitigate this and sustain long-term fat loss.
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