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Weight gain calculator
To gain weight, eat a calorie surplus: more than your maintenance. A lean bulk of about 0.25% of your body weight a week means roughly 150–300 calories a day above maintenance, enough to build muscle without much fat. For a 30-year-old man of 70 kg (154 lb) and 178 cm at 8,000 steps a day, maintenance is about 2,270, a lean bulk about 2,460 and the fastest sensible pace (0.5% a week) about 2,650. Lift weights so most of the gain is muscle.
What is a calorie surplus?
A calorie surplus means eating more calories than you burn. Your body stores the extra: as muscle if you train and eat enough protein, otherwise mostly as fat. About 7,700 extra calories add roughly 1 kg of weight, so a surplus of 250 a day is about 0.23 kg (0.5 lb) a week. The calculator starts from your maintenance, built from your steps and workouts (maintenance calorie calculator), and adds a surplus sized to your weight.
Calories to gain weight by body size
| Person | Maint. | Lean bulk+0.25%/wk | Faster+0.5%/wk |
|---|---|---|---|
| Woman, 50 kg 110 lb | 1,630 | 1,760 | 1,900 |
| Woman, 60 kg 132 lb | 1,800 | 1,960 | 2,130 |
| Man, 60 kg 132 lb | 2,110 | 2,280 | 2,440 |
| Man, 70 kg 154 lb | 2,270 | 2,460 | 2,650 |
| Man, 80 kg 176 lb | 2,440 | 2,660 | 2,880 |
| Man, 90 kg 198 lb | 2,620 | 2,870 | 3,120 |
How fast should you gain weight?
- New to lifting: up to 0.5% of your weight a week. Beginners build muscle fastest, so more of the surplus becomes muscle.
- A year or more of training: about 0.25% a week (lean bulk).
- Experienced lifters: about 0.1–0.15% a week; muscle comes slowly, and a bigger surplus mostly adds fat.
- Underweight, not lifting: 0.25–0.5% a week towards a healthy weight, with a doctor's advice if the weight loss was unexplained.
Women typically gain muscle at about half the rate of men, so the slower end suits most women. More in how many calories to build muscle.
Bulking calculator: calories and macros for a lean bulk
| Person | Calories | Protein | Carbs | Fat |
|---|---|---|---|---|
| Woman, 50 kg 110 lb | 1,760 | 90 g | 220 g | 60 g |
| Woman, 60 kg 132 lb | 1,960 | 110 g | 235 g | 65 g |
| Man, 60 kg 132 lb | 2,280 | 110 g | 320 g | 65 g |
| Man, 70 kg 154 lb | 2,460 | 125 g | 335 g | 70 g |
| Man, 80 kg 176 lb | 2,660 | 145 g | 355 g | 75 g |
| Man, 90 kg 198 lb | 2,870 | 150 g | 390 g | 80 g |
Protein builds the muscle (protein to build muscle); most of the extra calories go to carbs to fuel training. Your own split: the macro calculator. Bulk or cut first? See bulking vs cutting.
How long to gain 5 kg (11 lb)?
| Start weight | Slow0.15%/wk | Lean bulk0.25%/wk | Faster0.5%/wk |
|---|---|---|---|
| 50 kg 110 lb | 64 weeks | 39 weeks | 20 weeks |
| 60 kg 132 lb | 54 weeks | 33 weeks | 17 weeks |
| 70 kg 154 lb | 47 weeks | 28 weeks | 14 weeks |
| 80 kg 176 lb | 41 weeks | 25 weeks | 13 weeks |
Gaining weight when you're underweight
With a BMI under 18.5, gaining towards a healthy weight is good for bones, hormones and energy. Start with a slow or lean surplus and build up; people who find it hard to eat more do better with calorie-dense foods and drinks (how to gain weight). If you lost weight without trying, or can't gain despite eating more, see a doctor first: thyroid and digestive problems are common causes.
If the scale doesn't move
Many people who "can't gain" move more without noticing when they eat more, and they eat less at other meals than they think. Weigh in a few times a week, compare weekly averages, and add 150–200 calories if the trend is flat after 2–3 weeks (gaining with a fast metabolism).
Sources
- Iraki J, Fitschen P, Espinar S, Helms E. Nutrition recommendations for bodybuilders in the off-season: a narrative review. Sports 2019;7(7):154.
- Helms ER, Aragon AA, Fitschen PJ. Evidence-based recommendations for natural bodybuilding contest preparation: nutrition and supplementation. J Int Soc Sports Nutr 2014;11:20.
- Hall KD, Sacks G, Chandramohan D, et al. Quantification of the effect of energy imbalance on bodyweight. Lancet 2011;378(9793):826–837.