Result
Estimated time to reach 160 lb
20 weeks
140 days · about 4.6 months
- Total to lose20.0 lb
- Weekly loss rate0.45 kg/wk equivalent1.00 lb/wk
- % body weight per weekMedical consensus: 0.5–1% per week is sustainable; above 1% risks muscle loss and metabolic adaptation.0.56%Healthy
- Days to goal140 days
- 25% milestone weightReached around week 5175.0 lb
- 50% milestone weightReached around week 10170.0 lb
- 75% milestone weightReached around week 15165.0 lb
1.00 lb/wk — sustainable per CDC
Not medical advice — Estimate only — not medical advice. The 3,500-cal-per-pound rule overstates actual loss because TDEE drops as you lose weight (metabolic adaptation); real loss slows by 5-15% over 3 months. Consult a physician before any aggressive deficit, especially with diabetes, heart disease, eating-disorder history, or during pregnancy/breastfeeding.
How to use this calculator
- Pick units (lb or kg).
- Enter current weight and goal weight.
- Enter your daily calorie deficit — typically 500 cal/day for steady 1 lb/wk loss; 750 for ~1.5 lb/wk; 1,000 is aggressive.
- Read the timeline. If the % body weight per week badge turns yellow or red, reduce the deficit to stay sustainable.
About this tool
Weight loss is energy in minus energy out. A 500-cal/day deficit produces about 1 lb (0.45 kg) per week, by the long-standing rule that a pound of body fat stores roughly 3,500 calories. This calculator works backward from your goal: enter where you are, where you want to be, and how big a daily deficit you can sustain — it returns the target date, weekly loss rate, and a safety check against medical-consensus limits (CDC: 1-2 lb/wk; clinical guidance: under 1% of body weight per week to avoid muscle loss and metabolic slowdown).
Frequently asked
It is a useful approximation for short timeframes but overstates long-term loss. As you lose weight, your TDEE drops (smaller body burns fewer calories), so the same deficit produces less loss over time. Expect actual loss to be 5-15% slower than the linear estimate over 3+ months. Re-run the calculator with updated weight every few weeks.
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