Fat Loss Calculator — Start Now
A fat loss calculator estimates your daily calorie target and the weekly pace needed to reach your goal, so you know how much to eat and what a realistic timeline looks like.
Quick summary
This fat loss calculator estimates daily calories and expected weekly progress for a target goal. The page includes a timeline chart, formulas, examples, FAQs, and references for realistic planning.
Fat Loss Calculator
This fat loss calculator uses your age, sex, height, weight, and activity level to estimate maintenance calories, then applies your preferred weekly loss rate to set a daily calorie target. If you have not calculated maintenance before, start with the TDEE calculator for weight loss and return here to translate it into a weekly plan. The results show both pounds and kilograms so you can track progress in any unit.
A steady weekly rate keeps hunger and energy levels manageable. Many people begin around 0.5-1.0 lb (0.2-0.5 kg) per week and adjust after two to three weeks of consistent tracking. If you need help dialing in a specific calorie gap, the calorie deficit calculator is a helpful companion.
Calculator
Estimate your daily calories for fat loss using your stats and target weekly pace. The results include a timeline showing expected progress.
| Week | Total loss | Expected weight |
|---|---|---|
| 2 weeks | 2.0 lb | 0.9 kg | 163.0 lb | 73.9 kg |
| 4 weeks | 4.0 lb | 1.8 kg | 161.0 lb | 73.0 kg |
| 8 weeks | 8.0 lb | 3.6 kg | 157.0 lb | 71.2 kg |
| 12 weeks | 12.0 lb | 5.4 kg | 153.0 lb | 69.4 kg |
| 16 weeks | 16.0 lb | 7.3 kg | 149.0 lb | 67.6 kg |
Fat loss timeline chart
The chart below shows an example timeline using a 1 lb (0.45 kg) per week pace starting at 180 lb (81.6 kg). Use it as a reference, then personalize the timeline in the calculator above.
| Week | Total loss | Expected weight |
|---|---|---|
| 4 weeks | 4.0 lb | 1.8 kg | 176.0 lb | 79.8 kg |
| 8 weeks | 8.0 lb | 3.6 kg | 172.0 lb | 78.0 kg |
| 12 weeks | 12.0 lb | 5.4 kg | 168.0 lb | 76.2 kg |
| 16 weeks | 16.0 lb | 7.3 kg | 164.0 lb | 74.4 kg |
Fat loss formula
We estimate basal metabolic rate (BMR) with the Mifflin-St Jeor formula, then multiply by an activity factor to get maintenance calories (TDEE). Your weekly fat loss goal converts to a daily calorie deficit, which is subtracted from maintenance to set a target.
Activity factors range from 1.2 (sedentary) to 1.9 (athlete). A 10-20% deficit is common for steady fat loss, but the weekly loss input lets you match the pace to your lifestyle and training load.
Example calculation
Example: Female, 32 years old, 5'6" (168 cm), 165 lb (75 kg), moderately active (1.55). BMR = 10 × 75 + 6.25 × 168 − 5 × 32 − 161 = 1,487 kcal. TDEE = 1,487 × 1.55 = 2,305 kcal/day.
With a 1 lb weekly loss goal, daily deficit = 3,500 ÷ 7 = 500 kcal. Target calories = 2,305 − 500 = 1,805 kcal/day. After 8 weeks, the projected loss is about 8 lb (3.6 kg).
FAQ
What is a safe weekly fat loss rate?
Many people do well with 0.5-1.0 lb (0.2-0.5 kg) per week. Faster loss can be harder to sustain and may reduce training performance or recovery.
Should I change calories as weight drops?
Yes. Maintenance calories decrease as you lose weight. Update your inputs every 4-6 weeks or after a 5-10 lb change to keep the target accurate.
Why is my scale not moving every week?
Water retention, sodium, sleep, and menstrual cycles can mask fat loss. Look at 2-3 week trends before making adjustments.
Do I need cardio to lose fat?
Cardio helps create a deficit, but nutrition drives most of the change. Use the calories burned calculator for running to estimate how workouts affect your daily target.
Resources
These references outline evidence-based weight loss guidance and the formulas behind resting energy expenditure.
Evidence-based references: CDC: Healthy weight loss, NIDDK: Healthy eating and activity, PubMed: Predictive equation for resting energy expenditure.