Weight Loss Calculator Reddit | TDEE & Calorie Deficit Estimator
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Daily Calorie Target
2,200 kcal
Maintenance Calories (TDEE):
2,700 kcal
Daily Deficit:
-500 kcal
Est. Date to Reach Goal:
October 15, 2024
Formula: Mifflin-St Jeor Equation with activity multiplier.
Projection assumes consistent adherence to calorie deficit.
Calorie Intake for Different Goals
| Goal |
Weekly Change |
Daily Calories |
Values below 1200 kcal (women) or 1500 kcal (men) are generally not recommended without medical supervision.
What is the Weight Loss Calculator Reddit Users Recommend?
If you have spent any time browsing communities like r/loseit, r/fitness, or r/nutrition, you have likely seen discussions about the "best" calculator for shedding pounds. The weight loss calculator reddit users trust most is typically based on the Mifflin-St Jeor equation.
Unlike generic calculators that might overestimate calorie burns, the methodology favored by the Reddit community focuses on calculating your Total Daily Energy Expenditure (TDEE) accurately. This tool is designed for anyone—from complete beginners to advanced lifters—who wants a scientifically grounded estimate of how much they should eat to lose fat while preserving muscle.
Weight Loss Calculator Reddit: Formula and Mathematical Explanation
The core logic behind this calculator relies on determining your Basal Metabolic Rate (BMR) and then applying an activity multiplier. The community consensus is that the Mifflin-St Jeor equation is currently the most accurate for the general population.
Step 1: Calculate BMR
Your BMR is the number of calories your body burns just to exist (breathing, blood circulation, cell repair).
- Men: (10 × weight in kg) + (6.25 × height in cm) – (5 × age in years) + 5
- Women: (10 × weight in kg) + (6.25 × height in cm) – (5 × age in years) – 161
Step 2: Apply Activity Multiplier
Once BMR is known, we multiply it by an activity factor to find your TDEE (Maintenance Calories).
| Variable |
Meaning |
Standard Value / Range |
| Sedentary |
Office job, little to no exercise |
BMR × 1.2 |
| Lightly Active |
Light exercise 1–3 days/week |
BMR × 1.375 |
| Moderately Active |
Moderate exercise 3–5 days/week |
BMR × 1.55 |
| Very Active |
Heavy exercise 6–7 days/week |
BMR × 1.725 |
Step 3: Calculate the Deficit
To lose weight, you must consume fewer calories than your TDEE.
1 lb of fat ≈ 3,500 calories.
Therefore, a daily deficit of 500 calories results in approximately 1 lb of weight loss per week.
Practical Examples (Real-World Use Cases)
Example 1: The Office Worker (Sedentary)
Profile: John, 35 years old, 5'10" (178cm), 200 lbs (90.7kg), works a desk job.
- BMR Calculation: approx. 1,850 kcal/day.
- TDEE (Sedentary x 1.2): 2,220 kcal/day.
- Goal: Lose 1 lb per week.
- Target: 2,220 – 500 = 1,720 kcal/day.
Using the weight loss calculator reddit logic, John realizes he doesn't need to run a marathon to lose weight; he simply needs to stick to ~1,720 calories.
Example 2: The Active Professional
Profile: Sarah, 28 years old, 5'4″ (163cm), 150 lbs (68kg), goes to spin class 4 times a week.
- BMR Calculation: approx. 1,450 kcal/day.
- TDEE (Moderate Activity x 1.55): 2,250 kcal/day.
- Goal: Lose 0.5 lb per week (slow and steady).
- Target: 2,250 – 250 = 2,000 kcal/day.
Sarah can eat significantly more than John because of her high activity level, illustrating why inputting accurate activity data is crucial.
How to Use This Weight Loss Calculator Reddit Tool
- Enter Your Stats: Input your current age, gender, weight, and height. Be precise.
- Select Activity Level: Be honest. Most Redditors suggest choosing "Sedentary" if you have a desk job, even if you exercise occasionally, to avoid overestimating calories burned.
- Choose Your Goal: Select how much weight you want to lose per week. The standard recommendation is 1 lb (0.45 kg) per week.
- Review Results: The calculator will output your "Daily Calorie Target." This is the number you should track in apps like MyFitnessPal or Cronometer.
- Track and Adjust: Re-calculate every 5-10 lbs of weight loss, as your metabolic needs decrease as you get smaller.
Key Factors That Affect Weight Loss Results
When using a weight loss calculator reddit users discuss, keep these financial and physiological factors in mind:
- Metabolic Adaptation: As you lose weight, your body burns fewer calories. You must lower your intake over time to keep losing.
- Non-Exercise Activity Thermogenesis (NEAT): Fidgeting, walking, and standing affect your burn rate more than the gym does.
- Macronutrient Composition: Protein has a higher thermic effect than fats or carbs. A high-protein diet often yields better results than the calculator predicts.
- Water Weight: High sodium or carbohydrate intake can cause water retention, masking fat loss on the scale.
- Consistency vs. Perfection: Hitting your calorie target on average over the week is more important than being perfect every single day.
- Underestimating Intake: Most people underestimate how much they eat by 20-30%. If you aren't losing weight, you are likely eating more than you think.
Frequently Asked Questions (FAQ)
Is the weight loss calculator reddit method accurate?
Yes, the Mifflin-St Jeor equation is considered the gold standard. However, it is an estimate. You should adjust your intake based on real-world results after 2-3 weeks.
Why does Reddit recommend "Sedentary" activity?
Most fitness trackers and gym machines overestimate calories burned. Setting the calculator to "Sedentary" provides a safety buffer to ensure you remain in a deficit.
Can I lose 2 lbs a week?
It is possible, but often difficult and potentially muscle-wasting unless you have a high starting weight (obesity). A rate of 1% of body weight per week is a safer upper limit.
What if I stop losing weight?
You have hit a plateau. This usually means you have lost enough weight that your new maintenance calories equal your current intake. Recalculate your numbers with your new weight.
Should I eat back my exercise calories?
The general consensus on Reddit is no. Or, if you do, only eat back 50% of what your watch says you burned, as those devices are often inaccurate.
Does this calculator work for Keto or Intermittent Fasting?
Yes. Weight loss is fundamentally about Energy Balance (Calories In vs. Calories Out). Keto and Fasting are tools to help you adhere to the calorie limit this calculator provides.
What is "Starvation Mode"?
True starvation mode is rare in healthy individuals with body fat reserves. However, adaptive thermogenesis (metabolism slowing down) is real. This is why recalculating is necessary.
How important is protein?
Very. High protein intake helps preserve muscle mass while in a calorie deficit. Aim for 0.8g to 1g of protein per pound of lean body mass.
Related Tools and Internal Resources
Enhance your fitness journey with these related tools:
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" +
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