Weight Loss Calculator
See how long it will take to reach your goal weight and the daily calorie deficit required to get there safely.
Estimated time to goal
20 weeks
Target date: —
To lose
10 kg
Daily deficit
550 kcal
How the weight-loss timeline works
Fat loss comes down to energy balance. Because a pound of body fat stores roughly 3,500 calories (and a kilogram about 7,700), the size of your daily calorie deficit determines how quickly you lose weight. This calculator converts your chosen weekly rate into the daily deficit you'll need and projects a realistic target date.
The 3,500-calorie rule in practice
The 3,500-calorie rule is a useful starting point, but real-world results vary. Water retention, muscle gain, hormonal shifts, and metabolic adaptation all mean your actual weekly loss may differ from the mathematical projection. Use the result as a guide, not a guarantee, and adjust your intake based on 2–3 week trends rather than daily scale weight.
Choosing a sustainable pace
Faster isn't always better. Losing 0.5–1% of your body weight per week protects muscle and is far easier to maintain than crash dieting. If your required deficit feels too large, choose a gentler rate — slow, consistent progress wins. Learn more in the weight loss guide.
Setting up your calorie deficit
Your starting point is your maintenance calories. Find those with the TDEE calculator, then subtract your daily deficit to get your target intake. A deficit of about 500 calories per day produces roughly one pound of fat loss per week. Pair that with a high-protein macro split to preserve muscle while the fat comes off.
Combining diet with exercise
You can create your deficit through diet, exercise, or both. Moving more — walking, strength training, or cardio — gives you more calories to eat while still losing fat. Use the calories burned calculator to see how much your workouts contribute. For running, try the running calorie calculator; for walking, the walking calorie calculator; and for gym sessions, the treadmill calorie calculator. Even adding steps with a walking calorie calculator can add 100–300 calories of burn per day.
How to break through plateaus
If the scale stalls for more than 2–3 weeks, recalculate your TDEE at your new weight — it will be lower. Tighten your food tracking, add 10–15 minutes of activity, or reduce your deficit slightly to reset your metabolism. Small, consistent adjustments beat drastic cuts.
Common mistakes that slow weight loss
- Underestimating portions: Weighing and logging food removes guesswork.
- Forgetting liquid calories: Coffee drinks, smoothies, and cooking oils add up fast.
- Skipping strength training: Muscle is metabolically active; losing it slows your metabolism.
- Not recalculating: Your maintenance drops as you lose weight. Recalculate every 4–5 kg.
- Ignoring sleep: Poor sleep increases hunger hormones and weakens willpower.
Putting your plan into action
Use the calorie deficit calculator to find your exact daily deficit target, then the meal calorie calculator to split that target across breakfast, lunch, dinner, and snacks. For extra accountability, try the intermittent fasting calculator to fit meals into a shorter eating window.
Sources and further reading
These independent, authoritative sources inform the methods used on this page.
Frequently asked questions
How long will it take to lose weight?
It depends on your calorie deficit. A 500-calorie daily deficit produces about 0.45 kg (1 lb) of loss per week. This calculator estimates your timeline based on the weekly rate you choose and the total weight you want to lose.
What is a safe rate of weight loss?
Most experts recommend 0.5–1 kg (1–2 lb) per week, or about 0.5–1% of body weight. Faster loss raises the risk of muscle loss and is harder to sustain.
Why do I need a calorie deficit?
You lose fat when you consistently burn more calories than you eat. The shortfall forces your body to use stored fat for energy. A pound of fat stores roughly 3,500 calories.
Will my weight loss slow down?
Yes. As you lose weight your calorie needs fall, so the same intake produces a smaller deficit. Recalculate your targets every few weeks and stay patient through plateaus.
What is the best calorie deficit for fat loss?
A 250-500 calorie daily deficit works best for sustainable fat loss without muscle loss. Larger deficits often lead to hunger and metabolic slowdown.
How do I know if I'm in a calorie deficit?
Track your food intake and compare it to your TDEE. If you're losing 0.5-1 lb per week, you're in the right range. Use our calorie tracker or app.
Should I eat back calories burned exercising?
For weight loss, eat back about half of exercise calories to maintain energy and prevent overeating. Our calculator already accounts for activity level.
Can I speed up my weight loss timeline?
You can increase deficit through diet or exercise, but combined deficits over 1000 calories are hard to maintain. Better to increase activity slightly and stick to the plan.
Why am I not losing weight at the expected rate?
Common causes: underestimating food intake, overestimating activity, water retention, metabolic adaptation. Track everything precisely for 1-2 weeks.
How many calories should I eat to lose weight?
Subtract your desired deficit (usually 500) from your TDEE. If your TDEE is 2200, aim for 1700 calories daily for 1 lb/week loss.
What is a caloric weight loss calculator?
A caloric weight loss calculator like this one converts your weight loss goal into a daily calorie deficit and timeline. It uses the 3,500-calorie rule to estimate how long your goal will take.
What is a weight loss calculator predictor?
A weight loss calculator predictor estimates your future weight based on your current plan. This tool projects your target date from your chosen weekly rate and starting weight.
How does intermittent fasting affect weight loss?
Intermittent fasting can help control calories by limiting eating windows. Pair it with a moderate deficit for best results. Use the <a href='/intermittent-fasting-calculator/'>intermittent fasting calculator</a> to plan your schedule.
Does cardio help weight loss?
Cardio burns extra calories and supports heart health. Combine it with dietary changes for the fastest results. Use the <a href='/calories-burned-calculator/'>calories burned calculator</a> to estimate your exercise contribution.