Trying to lose weight? Our Calorie Deficit Calculator will show you how long it might take to reach your goal. Weight loss comes down to consuming fewer calories than you burn – a calorie deficit. Use this tool to estimate the timeline for your diet plan and set realistic expectations.

Calorie Deficit Weight Loss Calculator

Find out how long it might take to reach your goal weight:



kcal

How it works: A pound of body fat is roughly 3500 calories, and a kilogram is about 7700 calories. If you create a daily deficit (by eating less and/or exercising more), you’ll burn stored fat over time. For example, a 500-calorie daily deficit is often cited for losing about 1 lb per week. Our calculator uses your current weight and goal weight to find the total weight to lose, then calculates the time to lose that weight based on your chosen daily calorie deficit:

  • Input: your current weight, target weight, and how many calories you plan to cut per day.
  • Calculation: we compute total weight to lose (current – target). Then we multiply that by 7700 kcal/kg (if using kg) or 3500 kcal/lb to get the total calories needed to burn. Finally, we divide by your daily deficit to get the number of days.
  • Output: how many days, weeks, or months your journey might take.

Example: Suppose you weigh 80 kg and your goal is 70 kg – that’s 10 kg to lose. With a 500 kcal/day deficit, you’d need to burn about 77,000 kcal total. Dividing 77,000 by 500 gives 154 days, roughly 22 weeks or about 5 months. The calculator will show this as an estimate. This helps you see that healthy weight loss is a gradual process – about 0.5 kg (1 lb) per week in this case.

Remember, weight loss isn’t perfectly linear. Factors like water weight, metabolism changes, and diet adherence play a role. However, the estimate is a useful guideline. If the timeline seems too long, avoid the temptation to set an extreme deficit – very low calorie intakes can be unhealthy. Instead, consider a moderate deficit and focus on sustainable habits:

  • Combine diet with exercise to burn more calories safely.
  • Aim for 0.5–1 kg (1–2 lbs) of weight loss per week, which is generally considered healthy.
  • Reevaluate your calorie needs as you lose weight (smaller bodies burn fewer calories).

By planning with our Calorie Deficit Calculator, you can set achievable milestones and stay motivated on your weight loss journey. Patience and consistency are key – with time, you will see progress.