Goal date calculator
Estimate when you could reach your goal weight at a daily calorie target, with a simple projection and a slower, more realistic one that allows for your metabolism adapting as you lose weight.
Two projections, on purpose
The simple projection divides the weight to lose by your current daily deficit, using about 7,700 calories per kilogram. It is the number most calculators show, and it is too optimistic, because it assumes you burn the same amount at your goal weight as you do today.
The realistic projection recalculates your maintenance calories week by week as your weight falls, so the deficit shrinks over time. Research models of weight change (Hall and colleagues, 2011) describe this slowing in detail; this calculator uses a simplified week-by-week version of the same idea.
loss = (maintenance − intake) × 7 ÷ 7,700 kg
Leave the calorie box empty and the calculator assumes a 550-calorie daily deficit from today's maintenance.
Questions
How long will it take to reach my goal weight?
It depends on the size of your daily deficit. At about 550 calories a day below maintenance, many people lose around 0.5 kg (1 lb) a week at first. This calculator gives a simple estimate and a more realistic one that allows for loss slowing down.
Why is my real progress slower than the calculator?
Two reasons: as you get lighter you burn fewer calories, and water weight makes the scale noisy from day to day. Expect the second half of a goal to take longer than the first.
Is it safe to lose weight quickly?
Rapid loss is harder to sustain and makes it harder to meet nutrient needs. For most adults, 0.25–1 kg (0.5–2 lb) a week is the recommended range.
How can I make the estimate more accurate?
Track what you eat and weigh yourself several times a week. After three or four weeks, your own data shows your real rate of loss, which beats any formula.
Sources
- Hall KD, et al. Quantification of the effect of energy imbalance on bodyweight. Lancet. 2011;378(9793):826–837.
- Thomas DM, Martin CK, Heymsfield S, et al. A simple model predicting individual weight change in humans. J Biol Dyn. 2011;5(6):579–599.
Built and checked by Ingrid Solberg. Last reviewed October 22, 2026. All formulas: formulas & sources.