Free BMR & TDEE Calculator — Daily Calorie Needs (Mifflin-St Jeor)
November 2, 2026 · 3 min read · By the DollarWise team
How it works
Enter your gender, age, height, weight and activity level. This calculator estimates your Basal Metabolic Rate (BMR) with the widely used Mifflin-St Jeor equation, multiplies it by your activity factor to get your Total Daily Energy Expenditure (TDEE), and then shows the daily calorie targets for steady weight loss, maintenance and healthy weight gain.
## How the math works
Your BMR is the calories you burn at complete rest, estimated by the Mifflin-St Jeor equation — the most accurate widely-used formula for healthy adults:
**Men: BMR = 10 × weight(kg) + 6.25 × height(cm) − 5 × age + 5**
**Women: BMR = 10 × weight(kg) + 6.25 × height(cm) − 5 × age − 161**
Your TDEE multiplies BMR by an activity factor (1.2 sedentary up to 1.9 extra active) to include exercise and daily movement. A sustained 500 kcal/day deficit or surplus changes body mass by roughly 0.45 kg per week, which is how the loss and gain targets are derived.
## Everyday uses
- **Weight loss set-up:** pick the loss target as your daily calorie ceiling and track intake for 2–3 weeks to confirm.
- **Bulk planning:** use the gain target to add muscle without excessive fat gain, paired with strength training.
- **Dietary check:** if your weight is not changing, compare your actual intake to the maintenance number — the gap is usually smaller than you think.
## Frequently asked questions
### Which is more accurate, BMR or TDEE?
BMR is a resting estimate; TDEE is what you actually burn in a normal day and is the number to use for eating targets. TDEE is less precise because activity level is self-rated, so treat it as a starting point and adjust based on your real weight trend.
### Is a 500 kcal deficit safe for everyone?
A 500 kcal/day deficit is a common moderate target for most adults, but very short, light or older individuals may need a smaller deficit to avoid nutrient gaps. If you have medical conditions, are pregnant, or are under 18, consult a doctor or dietitian before restricting calories.
### Why does my weight change faster or slower than predicted?
The 0.45 kg/week rule assumes ~7,700 kcal per kg of body mass, but real changes include water weight, muscle gain/loss and metabolic adaptation. Weigh yourself under consistent conditions and look at the 2–3 week trend, not day-to-day fluctuations.