BMR Calculator
Calculate your Basal Metabolic Rate (BMR) and daily calorie needs based on your activity level
Personal Information
Your Results
Your Basal Metabolic Rate (BMR)
Calorie Needs by Activity Level
About BMR
What is BMR?
Basal Metabolic Rate (BMR) is the number of calories your body needs to accomplish its most basic (basal) life-sustaining functions at rest.
How is BMR Calculated?
We use the Mifflin-St Jeor Equation, which is considered the most accurate for calculating BMR:
For Women: BMR = 10 × weight(kg) + 6.25 × height(cm) – 5 × age(y) – 161
Using Your Results
Your BMR represents the calories you burn at complete rest. To maintain your current weight, multiply your BMR by your activity factor.
BMR Calculator—Get Your Basal Metabolic Rate Right Away (2025)
What is a calculator for BMR?
A BMR Calculator is a free, science-based tool that tells you how many calories your body needs to stay alive while it’s at rest. This is called your Basal Metabolic Rate (BMR). This BMR calculator employs the Mifflin-St. Jeor Equation, which is the most accurate for current application, gives you a specific baseline for your daily calorie needs based on your age, sex, weight, and height. This is important for losing weight, gaining muscle, or staying healthy.
Fill up your information and receive:
✅ Your BMR (calories burned when resting)
✅ Your Total Daily Energy Expenditure (TDEE) based on how active you are
✅ Your calorie goals for reducing, maintaining, or gaining weight
✅ Practical next-step advice
✅ No sign-up required
✅ 100% free
✅ Works on both mobile and desktop
How to Use the BMR Calculator
You don’t need to log in or pay to figure out your metabolic rate. Just follow these three easy steps:
Fill up Your Information
Biological sex: Male or Female (used in the formula)
Age: In years (for example, 32)
Weight: In pounds or kilos
In feet/inches or millimetres, height
Choose how active you want to be
Pick how much you do every day:
🛌 Sedentary (little or no activity)
🚶 Lightly active (light exercise 1–3 days/week)
🏃 Moderately active (moderate exercise 3–5 days/week)
🏋️ Very active (hard exercise 6–7 days/week)
🏆 Very active (intense exercise plus a profession that requires a lot of movement)
Get Your Results
See right away:
- BMR: How many calories do you burn while you are at rest
- TDEE: The number of calories you require each day
- Goals for losing, maintaining, or gaining weight, such as “Eat 1,900 kcal/day to lose 1 lb/week”
- Copy or reset with one click
- No need for an email
- Use it for free as often as you like
- Optimised for mobile
Why Should You Use a BMR Calculator in 2025?
If you guess how many calories you need, you’ll get frustrated since eating too little will make you lose muscle and eating too much will make you gain fat. The BMR calculator takes away the guesswork by:
- Giving a scientifically proven baseline (Mifflin-St Jeor > Harris-Benedict)
- Taking into account the slowing down of metabolism with age
- Taking into account how muscle mass and metabolism vary between men and women
- Adding activity level for real-world realism
- Helping people reach their long-term weight goals (0.5–2 lbs/week)
Great for those who are just starting to work out, athletes, people who want to lose weight, dietitians, and anybody who cares about their health.
For official guidance on metabolism and healthy weight management, refer to the National Institutes of Health (NIH) – Body Weight Planner .
Our BMR Calculator’s Main Features: It’s Free to Use, No hidden fees or subscriptions
✅ No Need to Sign Up – Start doing math right away
✅ The Mifflin-St. Jeor Equation is the best way to get an accurate BMR
✅ TDEE Integration: Total calories dependent on how you live
✅ Goal-Based Targets: Clear figures for losing, maintaining, or gaining weight
✅ Support for both Imperial (lbs/ft) and Metric (kg/cm) units
✅ Works well on mobile devices. Works with iPads, iPhones, and Android phones
✅ Safe and Private— No data is saved or shared
✅ No ads or pop-ups— A clean, health-focused UI
BMR and TDEE BMR Explained
Calories burnt when resting
1,420 kcal a day
TDEE
BMR times activity equals the number of calories you require each day.
2,000 kcal/day (quite active)
To lose weight, you need to eat 500 fewer calories than your TDEE.
1,500 calories a day
To gain weight, you need to eat 300 to 500 more calories than your TDEE.
2,300 to 2,500 kcal per day
Important: BMR only counts the body’s basic operations, not digestion, movement, or exercise.
Example from the real world:
Sex: Female
28 years old
140 pounds (63.5 kg)
5’5″ (165 cm) tall
Activity level: light
Calculator for BMR Output:
- 1,380 calories a day for BMR
- TDEE: 1,930 calories a day
- Eat 1,430 calories a day to lose 1 pound a week
- To stay the same weight, eat 1,930 calories a day
- To acquire weight, you need to eat between 2,230 and 2,430 calories a day
This insight helps you make better eating choices and plan more realistically.
Questions That Are Often Asked
What does BMR mean?
Your Basal Metabolic Rate (BMR) is the number of calories your body uses while it is completely at rest to keep you alive. This includes breathing, brain function, organ function, and more.
How reliable is this BMR calculator?
It employs the Mifflin-St Jeor Equation, which clinical tests have proven to be within 10% of measured BMR, making it more accurate than prior formulations.
Can I use it if I’m overweight or really muscular?
BMR formulae are only guesses. Very strong or overweight people may observe some differences, but it’s still the best place to start.
Does ageing change BMR?
Yes! After age 20, your metabolism slows down by about 2–3% per ten years. Our calculator takes this into account.
Is my information safe?
Yes. We never keep, track, or disclose what you enter. Your browser does all the math.
Can I use it on my phone?
Yes! Works perfectly on iPhone and Android—great for keeping track of things in the gym or in the kitchen.
What’s the difference between TDEE and BMR?
BMR: Calories burned when at rest
TDEE is the sum of your BMR and the calories you expend through exercise, digestion, and movement.
Who may use this calculator for BMR?
Great for people who want to lose weight, get exercise, or eat better, but not for diagnosing medical problems.
Can I use it to plan meals?
Yes! Use our Healthy Meal Planner with your TDEE to make meals that are balanced and low in calories.
Tools that are good for your health and fitness
These free, no-login tools can help you on your path to better health:
- Calories Burn Calculator – Keep track of how many calories you burn while working out
- BMI Calculator : Check your weight and your BMR at the same time
- Army Body Fat Calculator : Get a better idea of your body composition
- Meal Planner for Health : Make meals that fit your calorie needs
- Explore all tools at Toolsspark.com
In 2025, be sure you fuel your body with precision.
Knowing your figures is the first step to smart nutrition in 2025.
Our BMR Calculator tells you:
- A metabolic baseline that is backed by research
- Calorie goals that are unique to you
- Full privacy and simplicity of usage
No guessing. No fad diets.
One number is all you need to get started on your health journey.
The finest BMR calculator of 2025 is free, quick, and will always be private.