Intermittent Fasting Weight Loss Calculator
The Intermittent Fasting Weight Loss Calculator estimates your potential weight loss timeline based on your biometrics and chosen fasting protocol. This tool helps health-conscious individuals plan their journey by calculating calorie deficits and target dates. Whether you are comparing the 16:8 method to 20:4, setting a goal weight deadline, or adjusting your activity level, this calculator provides a clear roadmap. Stop guessing and start tracking your progress with data-driven projections.
How Projected Weight Loss Is Calculated
Projected weight loss is an estimate of how much body fat you will lose over a specific period by creating a calorie deficit through fasting. First, we determine your Basal Metabolic Rate (BMR) using the gold standard Mifflin-St Jeor Equation. This step is crucial because it establishes the calories your body needs at complete rest.
BMR = (10 × weight kg) + (6.25 × height cm) - (5 × age) + S
Where:
- S = +5 for men, -161 for women
Next, we multiply your BMR by your activity level to find your Total Daily Energy Expenditure (TDEE). Finally, we apply a fasting protocol percentage to your TDEE to find your daily deficit. We then convert this deficit into pounds using the 3,500 calorie rule. This scientifically grounded method helps you set realistic expectations for your journey.
What Your Projected Weight Loss Means
Your projected weight loss number represents the realistic amount of fat you can expect to drop if you strictly stick to your chosen eating window. Lose Weight Safely: A loss of 1 to 2 pounds per week is considered the gold standard for sustainable results. This rate usually indicates you are burning fat without sacrificing muscle mass or triggering metabolic slowdown.
Break a Plateau: If your calculated loss is under 0.5 pounds per week, try increasing your fasting window to 18:6 or adding 30 minutes of moderate exercise daily. Reach a Specific Goal: To lose 20 pounds in 4 months, aim for a steady loss of 1.25 pounds per week by strictly adhering to your calculated calorie deficit.
Important Note
Actual results may vary due to water retention, hormonal changes, or metabolic adaptation. It is normal for weight loss to stall temporarily even if you are following the plan correctly.
Disclaimer: This tool is for informational purposes only and is not a substitute for professional medical advice. Always consult a healthcare provider before starting any new diet or fasting program.
Monitor your progress weekly rather than daily to get an accurate trend, and adjust your fasting method if you consistently fall short of your target.