How Fast Should You Lose Weight? Working Back From a Goal Date to Daily Calories

The math

Daily deficit (kcal) = (current weight − goal weight) × 7,700 ÷ days left, treating 1 kg of fat as about 7,700 kcal (3,500 per lb). In practice your burn falls as you lose, so progress is slower than this (the numbers behind a plateau). Read the result as "at least this much".

A reasonable pace

The US CDC notes that people who lose about 1–2 lb (0.5–1 kg) a week at a gradual, steady pace are more likely to keep it off.
Scaled to body size, 0.5–1% of body weight per week is a common guide. At 70 kg that is 0.35–0.7 kg a week.
If a date would push your target far below your BMR, move the date. 800 kcal a day or less is a very low-calorie diet that needs medical supervision.

Example: 70.2 kg to 60 kg

Time frame	Daily deficit	Weekly pace	Verdict
55 days	−1,428 kcal	about −1.3 kg	Too fast — from a 2,211 kcal TDEE this drops below 800 kcal
157 days (~5 months)	−500 kcal	about −0.45 kg	About 0.6% of body weight a week
314 days (~10 months)	−250 kcal	about −0.22 kg	Slow but easy to sustain

At 55 days the daily intake falls to very-low-calorie territory. Stretch the same 10 kg over five months and a 500 kcal deficit is enough.

This guide is general nutrition information and a walk-through of the math, not medical advice. If you have a medical condition, are pregnant or breastfeeding, are under 18, or food and weight are causing you distress, talk to a doctor or registered dietitian first.

Working it out in the app

Goal weight 70.2 kg to 60.0 kg, −1,428 kcal/day to reach goal in 55 days, about −1.3 kg per week — Goal plan result

Enter a goal weight and date

On the Calculator tab in Calorie Calculator, tap "Goal weight" and enter a weight and a date. Right underneath you get lines like "−1,428 kcal/day to reach goal in 55 days" and "About −1.3 kg per week".

If the pace is steep, move the date

The app does not warn you about a steep result, so check it yourself: if the weekly pace is more than 1% of your body weight, push the date back. Your actual daily target is set by "Goal" above (Lose mild −250, Lose fast −500 and so on) and never goes below 1,000 kcal.

Weight trend chart with weight line, moving average and goal line — Goal line

Follow the goal line

Once a goal weight is set, the Weight log trend chart shows a goal line, and the Stats tab shows Goal progress (Stats opens for 24 hours after a rewarded ad).

FAQ

I have an event coming up and need to lose fast.

Crash losses before a date are mostly water and come back quickly. Go at a pace that fits the time you have, and talk to a doctor if you feel you need more.

The result shows a plus sign.

Your goal is above your current weight, so you need to eat more each day. See gaining weight.

Sources: CDC, Losing Weight · NIDDK, very low-calorie diet

Calorie Calculator: BMR TDEE

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