Weight Loss Timeline Calculator

Losing a kilogram of body weight takes an energy deficit of roughly 7,700 kcal (about 3,500 kcal per pound), so a weekly rate translates into a daily deficit:

Daily deficit = weekly weight loss (kg) × 7,700 ÷ 7

Your maintenance calories come from the Mifflin-St Jeor equation multiplied by your activity level — the same method as the TDEE Calculator — and your daily intake is maintenance minus that deficit. Because a lighter body burns fewer calories, the calculator also shows your maintenance calories at your goal weight and what you'd need to eat near the end of the plan.

Enter your sex, age, height, current weight, goal weight, and activity level. Then choose Weekly rate to see when you'd get there, or Target date to see what that date demands. Press Calculate timeline for your goal date, weekly rate, daily deficit, the calories to eat, and a table of projected weights along the way.

The CDC recommends a gradual pace of about 1–2 pounds (0.5–1 kg) per week. The evidence on keeping weight off is more mixed than often assumed: a 2014 randomized trial found that people who lost weight quickly regained it at about the same rate as people who lost it slowly. But very fast weight loss makes it harder to get enough protein and nutrients, and it raises the risk of problems such as gallstones. A common guideline is 0.5–1% of body weight per week, which means a heavier person can safely lose faster in absolute terms than a lighter one. The calculator flags plans that go beyond that, plans that push daily calories below a sensible floor, and goal weights below the healthy BMI range.

The 7,700 kcal per kg rule assumes a fixed conversion between calories and weight, but bodies adapt. Researchers at the US National Institutes of Health have shown this rule overestimates long-term loss, because as you get lighter you burn fewer calories at rest and in movement, so the same intake produces a smaller and smaller deficit. Early weeks often show faster drops from water and glycogen, and plateaus are normal later on.

Treat the date as a best case for a plan you follow consistently, and re-run the numbers every few weeks with your new weight.

Calorie estimates are population averages and don't account for genetics, muscle mass, medication, or medical conditions. This tool is for healthy adults and is not suitable for children, or during pregnancy or breastfeeding. Rapid weight loss and very-low-calorie diets carry real risks and belong under medical supervision. Talk to a doctor or registered dietitian before making significant changes to your diet — see the Disclaimer for details, and use the Macro Calculator to split your daily calories into protein, carbs, and fat.

The formulas and figures on this page come from these sources. Our Editorial Policy explains how they're chosen and checked.

• About 7,700 kcal per kg (3,500 kcal per lb): Wishnofsky, M. (1958). Caloric equivalents of gained or lost weight. The American Journal of Clinical Nutrition, 6(5), 542–546. doi:10.1093/ajcn/6.5.542
• Maintenance calories: Mifflin, M. D., St Jeor, S. T., Hill, L. A., Scott, B. J., Daugherty, S. A., & Koh, Y. O. (1990). A new predictive equation for resting energy expenditure in healthy individuals. The American Journal of Clinical Nutrition, 51(2), 241–247. doi:10.1093/ajcn/51.2.241
• Activity levels and their typical PAL values (1.4, 1.6, 1.75, 2.05): National Academies of Sciences, Engineering, and Medicine. (2023). Dietary reference intakes for energy. The National Academies Press. doi:10.17226/26818
• 1–2 lb (0.5–1 kg) a week: Centers for Disease Control and Prevention. Steps for losing weight. Healthy Weight and Growth. Link
• 0.5–1% of body weight a week: Helms, E. R., Aragon, A. A., & Fitschen, P. J. (2014). Evidence-based recommendations for natural bodybuilding contest preparation: Nutrition and supplementation. Journal of the International Society of Sports Nutrition, 11, 20. doi:10.1186/1550-2783-11-20
• Fast vs. slow weight loss and regain: Purcell, K., Sumithran, P., Prendergast, L. A., Bouniu, C. J., Delbridge, E., & Proietto, J. (2014). The effect of rate of weight loss on long-term weight management: A randomised controlled trial. The Lancet Diabetes & Endocrinology, 2(12), 954–962. doi:10.1016/S2213-8587(14)70200-1
• Why the 7,700 kcal rule overestimates long-term loss: Hall, K. D., Sacks, G., Chandramohan, D., Chow, C. C., Wang, Y. C., Gortmaker, S. L., & Swinburn, B. A. (2011). Quantification of the effect of energy imbalance on bodyweight. The Lancet, 378(9793), 826–837. doi:10.1016/S0140-6736(11)60812-X
• Limits of the 3,500 kcal rule: Thomas, D. M., Martin, C. K., Lettieri, S., Bredlau, C., Kaiser, K., Church, T., Bouchard, C., & Heymsfield, S. B. (2013). Can a weight loss of one pound a week be achieved with a 3500-kcal deficit? Commentary on a commonly accepted rule. International Journal of Obesity, 37(12), 1611–1613. doi:10.1038/ijo.2013.51
• Early water and glycogen loss: Kreitzman, S. N., Coxon, A. Y., & Szaz, K. F. (1992). Glycogen storage: Illusions of easy weight loss, excessive weight regain, and distortions in estimates of body composition. The American Journal of Clinical Nutrition, 56(1 Suppl.), 292S–293S. doi:10.1093/ajcn/56.1.292S
• Daily floor of 1,200 kcal (women) and 1,500 kcal (men) without medical supervision: Harvard Health Publishing. (2024, April 3). Calorie counting made easy. Harvard Medical School. Link
• Healthy BMI range: World Health Organization. (2000). Obesity: Preventing and managing the global epidemic. Report of a WHO consultation (WHO Technical Report Series No. 894). Link