Basal Metabolic Rate (BMR) Calculator
Easy Basal Metabolic Rate (BMR) Calculator: What It Is and How to Use It for Weight Management
What is Basal Metabolic Rate (BMR)?
Basal Metabolic Rate (BMR) is the number of calories your body needs to maintain vital functions, such as breathing and maintaining body temperature, while at rest. It accounts for most of your daily calorie expenditure and serves as a foundation for estimating your Total Daily Energy Expenditure (TDEE), factoring in activity level.
Why use an online BMR calculator?
Manual calculation using BMR formulas can be complicated. An online BMR calculator simplifies this process, allowing you to enter your age, gender, height, and weight and receive an instant, accurate estimate of your daily calorie needs. This tool helps with:
- Personalized weight management plans
- Understanding calorie needs for fat loss or muscle gain
- Tracking changes as body composition evolves
How does the BMR calculator work?
The calculator applies the Mifflin-St Jeor equation:
- For men:
BMR = 10 × weight(kg) + 6.25 × height(cm) – 5 × age(years) + 5 - For women:
BMR = 10 × weight(kg) + 6.25 × height(cm) – 5 × age(years) – 161
By simply inputting your data, you get an accurate estimate of calories burned daily while at rest.
Why is knowing your BMR important?
Understanding your BMR helps you create realistic nutritional and fitness goals. Whether you're aiming to lose weight, maintain your current weight, or bulk up, knowing how many calories your body naturally burns enables smarter calorie intake and expenditure decisions. Combined with activity levels, this leads to precise calorie budgeting.
Features of our free BMR calculator script
- Easy-to-use interface with inputs for gender, age, height, and weight
- Instant, accurate results using a trusted scientific formula
- Mobile-responsive design for use on any device
- Privacy-first approach with client-side calculations—your data never leaves your device
Try it now
Use our BMR calculator embedded on your website or personal blog to empower yourself and your audience with personalized nutrition insight. Simply enter your information and let the calculator do the math.