Free Health Tools
Understand your body,
one number at a time
Two simple, science-based calculators to help you check your BMI and find your daily calorie target — free, instant, and no sign-up required.
100% Free
No Sign-up
Results in Seconds
BMI Calculator
Check your Body Mass Index in seconds and see where you fall on the healthy weight range for your height.
- Metric & imperial units
- Personalised by age & gender
- Shows your healthy weight range
Calorie Calculator
Get your personalised daily calorie target and a full macro breakdown using the Mifflin–St Jeor equation.
- BMR, TDEE & activity breakdown
- 5 goals, from fat loss to lean gain
- Protein, carb & fat targets included
Why use our calculators
Built to be quick, accurate, and easy to trust.
Instant results
No sign-up, no email required. Enter your details and get your result immediately.
Evidence-based formulas
Powered by established, peer-reviewed methods like the Mifflin–St Jeor equation — not guesswork.
Private by design
Everything runs in your browser. Your numbers are never stored or sent anywhere.
Frequently asked questions
Everything you need to know before you calculate.
How accurate is a BMI calculator?
BMI is a quick screening tool based on height and weight, not a diagnosis. It’s a reliable general indicator for most adults, but it doesn’t account for muscle mass, bone density, or body composition — so athletes or very muscular people may see a higher number than their actual body fat suggests. Use it as a starting point, and talk to a doctor for a complete picture of your health.
How is my daily calorie target calculated?
We use the Mifflin–St Jeor equation, widely regarded as the most accurate formula for estimating basal metabolic rate (BMR). Your BMR is then combined with your activity level to estimate total daily energy expenditure (TDEE), and adjusted for your goal — whether that’s fat loss, maintenance, or muscle gain.
What’s the difference between the BMI and Calorie calculators?
BMI shows where your current weight sits relative to your height. The Calorie Calculator goes further, estimating how much energy your body needs each day and how many calories to eat to lose, maintain, or gain weight. Many people use both together: check your BMI first, then use the calorie target to work toward a healthy range.
Are the calculators really free, with no sign-up?
Yes. Both tools are 100% free, with no account, no email address, and no hidden usage limits. Use them as often as you like.
Is my health data stored or shared anywhere?
No. Both calculators run entirely in your browser. We never collect, store, or transmit the numbers you enter — closing the tab clears everything.
How often should I recalculate my BMI or calorie needs?
It’s worth recalculating whenever your weight changes noticeably, or every 4–6 weeks if you’re actively working toward a goal. Age, activity level, and weight all shift the result over time, so treat it as a periodic check-in rather than a one-time number.