How fast should I lose weight?

Most health guidelines recommend losing no more than about 0.5–1 kg (1–2 lb) per week for sustainable, mostly fat-based weight loss.

What if my timeframe is too short?

If your timeframe requires losing weight faster than 1.5 kg per week, the calculator will flag it — try extending your timeframe to a safer, more realistic pace.

How do I turn the deficit into a meal plan?

Subtract the daily deficit shown from your maintenance calories (from the TDEE Calculator) to get a daily calorie target, then use that as a guide for your food intake.

Health & Fitness

Weight Loss Calculator

Enter your current weight, goal weight, and a timeframe to see the weekly loss rate and daily calorie deficit needed to reach your goal safely.

Your calculation is performed in your browser.

Enter your current weight, goal weight, and timeframe above.

This result is an estimate for informational and educational purposes. It isn’t a diagnosis and isn’t a substitute for advice from a doctor, registered dietitian, or other qualified professional. See our methodology and sources for the formula used and its limitations.

How it works

The calculator divides the total weight you want to lose by your chosen timeframe to find the required weekly loss rate, then converts that rate into a daily calorie deficit using the standard energy value of body fat. It flags timeframes that would require an unsafe rate of loss.

Formula & methodology

The total weight to lose is spread evenly over your timeframe to give a weekly rate. That rate is converted into a daily calorie deficit using about 7,700 calories per kg of fat (3,500 per lb). Plans needing more than 1.5 kg (3.3 lb) per week are rejected as unsafe.

Total to loseTotal to lose = Current weight − Goal weight

Weekly rateWeekly rate = Total to lose ÷ Weeks

Daily deficitDaily deficit = Weekly rate × Calories per unit ÷ 7

What each term means

Weeks: Your chosen timeframe.
Calories per unit: 7,700 per kg, or 3,500 per lb.

Worked example

Losing 10 kg over 20 weeks requires a rate of 0.5 kg per week, which needs a daily calorie deficit of about 550 calories.

Common uses

—Setting a realistic timeline for an upcoming event, like a wedding or holiday, around a weight goal.
—Checking whether a desired weight loss target is achievable at a safe weekly rate.
—Turning a goal weight and deadline into an actionable daily calorie deficit.

Important notes

—The calculator will not accept a timeframe that requires losing more than 1.5 kg (about 3.3 lb) per week, as this is generally not considered safe or sustainable.
—The daily deficit shown is relative to your maintenance calories — subtract it from your TDEE to get a target intake.