BMR Calculator Online – Calculate Your Basal Metabolic Rate Free
Advanced BMR Calculator
Spluxly’s free online BMR Calculator helps you find out exactly how many calories your body burns at complete rest. Using the scientifically trusted Mifflin-St Jeor Equation, it calculates your Basal Metabolic Rate (BMR) in kcal/day based on your age, weight, height, and gender. It then adjusts your results across multiple activity levels — from sedentary to extremely active — so you know precisely how many calories your body needs each day. Whether you’re planning a diet, building a fitness routine, or simply understanding your metabolism, this tool gives you accurate, instant results for free.
How to Use the BMR Calculator Online
Calculating your BMR is fast, simple, and requires no sign-up. Just follow these steps:
- Select Unit System – Choose Metric (kg, cm) or Imperial (lbs, in)
- Choose Gender – Select Male or Female
- Enter Age – Input your age in years (e.g., 30)
- Enter Weight – Add your current body weight (e.g., 70 kg or 154 lbs)
- Enter Height – Add your height (e.g., 170 cm or 67 in)
- Click Calculate – Instantly view your BMR in kcal/day, a full activity-level calorie table, and a visual bar chart
Why Use Spluxly’s BMR Calculator?
- Mifflin-St Jeor Formula – The most accurate and scientifically validated method for calculating BMR
- Activity-Level Calorie Table – See your daily calorie needs across all five activity levels in one view
- Visual Bar Chart – Easily compare calorie requirements at a glance for smarter diet planning
- Gender-Specific Results – Separate and accurate calculations tailored for both male and female users
- Metric & Imperial Support – Seamlessly switch between unit systems with instant conversions
- 100% Free & Instant – No registration, no fees — accurate results delivered in seconds