Calorie needs for a 100kg female
Estimated daily calorie needs for a female weighing 100kg at 170cm, moderately active.
Different stats? Use the full calorie calculator for your exact numbers.
About this calorie calculator
This calculator starts by estimating your Basal Metabolic Rate (BMR) — the number of calories your body burns at complete rest just to keep your heart beating, lungs breathing, and cells functioning — using the Mifflin–St Jeor equation. Developed in 1990 and validated repeatedly since, it's considered one of the most accurate BMR formulas for the general population, outperforming older equations like Harris-Benedict for most body types.
From there, it multiplies your BMR by an activity multiplier that reflects how much you move in a typical week, giving you your Total Daily Energy Expenditure (TDEE) — the calories you burn on an average day including exercise, walking, fidgeting, and digestion. TDEE is your maintenance number: eating roughly this many calories keeps your weight stable over time.
Unlike a calculator built around a single goal, this tool shows your calorie target across five common goals at once — from an aggressive 500-calorie surplus for muscle gain down to a 500-calorie deficit for weight loss — so you can see the full picture and choose a pace that fits your lifestyle without recalculating for every scenario.
Keep in mind that BMR and TDEE are estimates based on population averages. Your actual metabolism is influenced by muscle mass, genetics, hormones, sleep quality, and even the weather. Treat the numbers here as a starting point, track your real-world results over two to three weeks, and adjust your intake up or down based on how your weight actually changes.
This calculator is intended for general educational use and is not a substitute for personalized medical or nutritional advice. If you have a medical condition, are pregnant or breastfeeding, or are considering a significant change to your diet, talk to a doctor or registered dietitian first.
Calorie calculator questions
How BMR, TDEE, and your calorie goals are calculated.
How many calories do I need per day?
It depends on your BMR (calories burned at rest) and how active you are. This calculator multiplies your BMR by an activity factor to estimate your Total Daily Energy Expenditure (TDEE) — the calories you'd eat to maintain your current weight.
What's the difference between BMR and TDEE?
BMR is the energy your body needs at complete rest — just to keep organs functioning. TDEE adds in everything else: exercise, walking, work, and digestion. TDEE is always higher than BMR and is the number to use for daily calorie planning.
How is BMR calculated here?
This calculator uses the Mifflin–St Jeor equation, a well-validated formula based on your weight, height, age, and gender. It's generally considered more accurate than older formulas like Harris-Benedict for most adults.
How many calories should I eat to lose weight?
A 500-calorie daily deficit below your TDEE (shown as "Weight loss" in the goals table) typically produces about 0.5 kg (roughly 1 lb) of fat loss per week — a pace considered sustainable by most nutrition guidelines. A 250-calorie deficit ("Mild weight loss") is a gentler option.
How many calories should I eat to gain weight?
Eating 250–500 calories above your TDEE typically supports gradual weight gain. Combining a surplus with resistance training helps ensure more of that gain is muscle rather than fat.
Why does my activity level matter so much?
Activity level is the biggest lever in this calculation after body size. Moving from "sedentary" to "very active" can raise your TDEE by several hundred calories a day, which changes every goal in the table below it.
Is this calculator accurate for everyone?
It's a population-based estimate. Individual metabolism varies with muscle mass, genetics, hormones, and health conditions, so treat the result as a starting point and adjust based on how your weight actually trends over a few weeks.
Is this medical advice?
No. This tool provides general estimates for educational purposes only and isn't a substitute for personalized guidance from a doctor or registered dietitian, especially if you have a medical condition or specific nutrition needs.