Calorie Deficit Calculator
Calculate how long it will take to reach your goal weight. Get your daily calorie target and projected timeline.
How much calorie deficit to lose 0.5kg per week?
To lose 0.5kg/week, create a 500 calorie daily deficit (3,500 cal/week). For 1kg/week, you need a 1,000 cal/day deficit. The deficit is calculated by subtracting your target calories from your TDEE (total daily energy expenditure).
TL;DR
- •Calorie deficit = TDEE - daily intake. 500 kcal/day ≈ 0.45 kg/week fat loss (Mifflin-St Jeor formula)
- •Aggressive deficit (>750 kcal/day): faster loss but more muscle loss + hunger; not sustainable past 8-12 weeks
- •Moderate deficit (300-500 kcal/day): preserves muscle, sustainable for cuts up to 16 weeks, recommended
- •Inputs: age + weight + height + activity level → daily calorie target + 4-week timeline
- •Free, no signup. Result in 60s. Adjust every 2-3 weeks based on actual scale movement
Calculate Your Timeline
Enter your details to see your weight change timeline
Calculate how long it will take to reach your goal weight
About Calorie Deficits
1 kg of body fat contains approximately 7,700 calories. To lose 0.5 kg per week, you need a daily deficit of about 550 calories.
Safe rate of loss: 0.5-1% of body weight per week. Faster rates may lead to muscle loss, metabolic adaptation, and nutrient deficiencies.
Minimum calories: Women shouldn't go below 1,200 kcal/day and men below 1,500 kcal/day without medical supervision.
Note: These are estimates. Real-world weight loss varies due to water retention, muscle changes, and metabolic adaptation. Weigh yourself weekly and adjust calories based on actual progress.
Related Tools
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Arvo monitors your actual weight changes, adjusts calories based on results, and keeps you on track.
- Automatic progress tracking
- Calorie adjustments
- Personalized coaching
Want to Learn More?
Dive deeper into the science of fat loss and nutrition with our comprehensive guides.
The Calorie Deficit Formula
Understanding the math behind weight loss helps you set realistic expectations:
Where TDEE (Total Daily Energy Expenditure) is the total calories your body burns per day, and Deficit is the calorie reduction needed to lose weight.
Un déficit ne fonctionne que si l'estimation de votre TDEE est précise — déterminez votre base avec notre calculateur TDEE, puis fixez votre objectif en dessous.
This is the energy stored in 1kg of adipose tissue
7,700 ÷ 14 days = 550 calories per day
Safe middle ground for most people
More aggressive, requires discipline
Example Calculation
Your TDEE is 2,400 calories and you want to lose 0.5kg per week:
- 1Required deficit: 7,700 ÷ 14 = 550 calories/day
- 2Daily target: 2,400 − 550 = 1,850 calories/day
- 3Weekly deficit: 550 × 7 = 3,850 calories/week
Practical Examples: Your Weight Loss Timeline
Here's how long different weight loss goals typically take with a sustainable approach:
Lose 5kg
10-20 weeks (0.25-0.5 kg/week)
7-10 weeks (0.5-0.75 kg/week)
Great for small adjustments or maintaining muscle while cutting
Lose 10kg
20-40 weeks (5-10 months)
14-20 weeks (3.5-5 months)
Include 1-2 diet breaks for better adherence
Lose 15kg
30-60 weeks (7-15 months)
20-30 weeks (5-7.5 months)
Plan for 2-3 maintenance phases to prevent metabolic adaptation
Lose 20kg+
40-80 weeks (10-20 months)
27-40 weeks (6.5-10 months)
Lifestyle change mindset - this is a marathon, not a sprint
💡 These timelines assume consistent adherence. Real progress includes plateaus, social events, and life happening. Add 20-30% buffer time for realistic expectations.
Recommended Calorie Deficits by Body Type
Your ideal deficit depends on how much fat you have to lose. Leaner individuals need smaller deficits to preserve muscle:
| Body Fat % | Recommended Deficit | % of TDEE | Notes |
|---|---|---|---|
| Men >25% / Women >35% | 750-1000 cal | 25-30% | Higher body fat = larger safe deficit |
| Men 20-25% / Women 28-35% | 500-750 cal | 20-25% | Moderate deficit, good balance |
| Men 15-20% / Women 22-28% | 400-500 cal | 15-20% | Slower loss, better muscle retention |
| Men 12-15% / Women 18-22% | 300-400 cal | 10-15% | Minimize muscle loss priority |
| Men <12% / Women <18% | 200-300 cal | 5-10% | Very slow cuts, competition prep |
⚠️ Never go below 1,200 calories/day (women) or 1,500 calories/day (men) without medical supervision. Extreme deficits cause muscle loss, hormonal issues, and nutrient deficiencies.
Understanding Calorie Deficits
A calorie deficit occurs when you consume fewer calories than your body burns. This forces your body to use stored energy (fat) for fuel, resulting in weight loss.
The size of your deficit determines how quickly you lose weight. A larger deficit means faster weight loss, but also increases the risk of muscle loss, fatigue, and metabolic adaptation.
Recommended Rates of Weight Loss
The optimal rate depends on your starting point and goals:
| Rate | Type | Best For |
|---|---|---|
| 0.25-0.5 kg/week | Conservative | Best for those with less to lose, athletes, or those prioritizing muscle retention |
| 0.5-0.75 kg/week | Moderate | Good balance of speed and sustainability for most people |
| 0.75-1 kg/week | Aggressive | Suitable for those with significant weight to lose, requires discipline |
| >1 kg/week | Not recommended | High risk of muscle loss, metabolic adaptation, and nutrient deficiencies |
The Science Behind Weight Loss
Energy Balance
Weight loss is fundamentally about energy balance. 1 kg of body fat contains approximately 7,700 calories of stored energy.
Metabolic Adaptation
As you lose weight, your body adapts by burning fewer calories. This is why weight loss often slows down over time.
Non-Linear Progress
Weight loss isn't linear. Water retention, hormones, and digestive contents cause daily fluctuations of 1-2 kg.
Muscle Matters
Muscle burns more calories at rest. Preserving muscle through protein intake and resistance training keeps your metabolism higher.
Tips for Successful Weight Loss
- Track your food intake accurately using a food scale and calorie tracking app
- Weigh yourself at the same time each day (morning, after bathroom) and look at weekly averages
- Prioritize protein (1.6-2.2g per kg of body weight) to preserve muscle
- Strength train 2-4 times per week to maintain muscle mass
- Get 7-9 hours of quality sleep per night
- Include diet breaks (1-2 weeks at maintenance) every 8-12 weeks for long diets
Common Calorie Deficit Myths Debunked
❌ Cutting more calories means faster fat loss
✅ Extreme deficits cause muscle loss and metabolic adaptation. A moderate deficit (300-750 cal) preserves muscle and is more sustainable.
❌ Your metabolism slows down permanently in a deficit
✅ Metabolic adaptation is modest (5-15%) and reversible. NEAT (daily activity) drops more than metabolism itself. Both return to normal when eating resumes.
❌ You must eliminate carbs to lose fat
✅ No macronutrient must be eliminated. Caloric deficit is what matters for fat loss. Carbs support training performance and can be part of any successful diet.
❌ Eating at night makes you gain weight
✅ Meal timing doesn't affect fat loss - total daily calories do. Late eating only matters if it leads to overeating.
❌ You can target where you lose fat
✅ Spot reduction doesn't exist. Fat loss occurs systemically based on genetics. You can't choose to lose belly fat first.
Frequently Asked Questions
Comment calculer mon déficit calorique ?
Pour calculer votre déficit calorique : (1) Déterminez votre TDEE (dépense énergétique journalière totale), (2) Soustrayez 300-750 calories selon la vitesse de perte souhaitée, (3) Le résultat est votre objectif calorique quotidien pour perdre du poids. Notre calculateur le fait automatiquement.
Combien de temps faudra-t-il pour perdre du poids ?
La durée dépend du poids que vous voulez perdre et de votre rythme de perte. Un rythme sûr est de 0,5-1% du poids corporel par semaine. Par exemple, perdre 10kg à 0,5kg/semaine prend environ 20 semaines (5 mois).
Qu'est-ce qu'un déficit calorique sûr ?
Un déficit sûr se situe généralement entre 300 et 750 calories sous votre TDEE. Cela correspond à une perte de 0,25-0,75 kg (0,5-1,5 lb) par semaine. Descendre sous 1200 calories/jour pour les femmes ou 1500 pour les hommes n'est pas recommandé sans suivi médical.
Vais-je perdre du muscle avec un déficit calorique ?
Vous pouvez minimiser la perte musculaire en : (1) Gardant un déficit modéré (pas extrême), (2) Mangeant suffisamment de protéines (1,6-2,2g par kg de poids corporel), (3) Pratiquant régulièrement la musculation, (4) Dormant suffisamment.
Quelle est la précision de ce calculateur ?
Le calculateur fournit des estimations basées sur des formules établies. Les résultats réels varient en raison de l'adaptation métabolique, des fluctuations de rétention d'eau et des différences individuelles. Pesez-vous chaque semaine et ajustez les calories selon vos progrès réels.
Qu'est-ce que le TDEE et pourquoi en ai-je besoin ?
Le TDEE (dépense énergétique journalière totale) est le nombre total de calories que vous brûlez par jour. Pour perdre du poids, vous devez manger moins de calories que votre TDEE. Utilisez notre calculateur TDEE pour trouver le vôtre.
Combien de calories dans 1kg de graisse corporelle ?
Un kilogramme de graisse corporelle contient environ 7 700 calories (soit environ 3 500 calories par livre). Pour perdre 1kg par semaine, il faut donc un déficit quotidien d'environ 1 100 calories. Pour 0,5kg par semaine, un déficit quotidien de 550 calories suffit.
Dois-je remanger les calories brûlées à l'entraînement ?
Cela dépend de vos objectifs. Pour perdre du poids, évitez de remanger toutes les calories d'exercice, car les trackers surestiment souvent la dépense. Une approche prudente consiste à remanger 50% des calories d'exercice suivies. Si vous perdez du poids trop vite ou vous sentez fatigué, mangez-en davantage.
Pourquoi ma perte de poids stagne-t-elle ?
Les plateaux surviennent pour plusieurs raisons : (1) Adaptation métabolique — votre corps brûle moins de calories à mesure que vous perdez du poids, (2) Rétention d'eau accrue, (3) Sous-estimation des apports alimentaires. Pour les surmonter : recalculez votre TDEE à votre nouveau poids, faites une pause diététique de 1-2 semaines, ou augmentez votre activité.
1 200 calories, est-ce trop peu ?
Pour la plupart des gens, 1 200 calories est trop peu et peut entraîner des carences nutritionnelles, une perte musculaire et un ralentissement métabolique. Les femmes ne devraient généralement pas descendre sous 1 200 kcal/jour et les hommes sous 1 500 kcal/jour sans suivi médical. Un déficit modéré est plus durable à long terme.
Automatic Calorie Tracking
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