/** * Handle the Contact page form submission and email it to the site admin. */ function hc_handle_contact_submit() { if ( ! isset( $_POST['hc_contact_nonce'] ) || ! wp_verify_nonce( $_POST['hc_contact_nonce'], 'hc_contact_submit' ) ) { wp_safe_redirect( add_query_arg( 'contact', 'error', home_url( '/contact/' ) ) ); exit; } // Honeypot field: real users never fill this in. if ( ! empty( $_POST['hc_website'] ) ) { wp_safe_redirect( add_query_arg( 'contact', 'success', home_url( '/contact/' ) ) ); exit; } $name = isset( $_POST['name'] ) ? sanitize_text_field( wp_unslash( $_POST['name'] ) ) : ''; $email = isset( $_POST['email'] ) ? sanitize_email( wp_unslash( $_POST['email'] ) ) : ''; $message = isset( $_POST['message'] ) ? sanitize_textarea_field( wp_unslash( $_POST['message'] ) ) : ''; if ( empty( $name ) || empty( $message ) || ! is_email( $email ) ) { wp_safe_redirect( add_query_arg( 'contact', 'error', home_url( '/contact/' ) ) ); exit; } $to = get_option( 'admin_email' ); $subject = sprintf( '[Health Calculators] New contact message from %s', $name ); $body = "You have a new message from the Health Calculators contact form.\n\n" . "Name: {$name}\n" . "Email: {$email}\n\n" . "Message:\n{$message}\n"; $headers = array( 'Content-Type: text/plain; charset=UTF-8', "Reply-To: {$name} <{$email}>" ); $sent = wp_mail( $to, $subject, $body, $headers ); wp_safe_redirect( add_query_arg( 'contact', $sent ? 'success' : 'error', home_url( '/contact/' ) ) ); exit; } add_action( 'admin_post_hc_contact_submit', 'hc_handle_contact_submit' ); add_action( 'admin_post_nopriv_hc_contact_submit', 'hc_handle_contact_submit' ); Free Health & Fitness Calculators Online | Health Calculators
21 free tools · 2M+ calculations run

Your Free Health & Fitness Calculator Toolkit

Calculate BMI, calories, macros, and more. 21 free tools to help you plan, track, and reach your health goals faster.

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100% free · No sign-up required · Instant results

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FITNESS & EXERCISE

Fitness & Exercise Calculators

6 tools to track training, metabolism, and body composition.

BMI Calculator

Check if your weight is healthy for your height.

BMR Calculator

See how many calories your body burns at rest.

TDEE Calculator

Find your Total Daily Energy Expenditure.

Calories Burned

Track calories burned during workouts.

Body Fat %

Estimate body fat using standard formulas.

Fitness Progress

Track your weight and fitness journey.

NUTRITION & DIET

Nutrition & Diet Calculators

6 tools to plan calories, macros, and hydration.

Daily Calorie Needs

Calories to maintain, lose, or gain weight.

Protein Intake

Find your daily protein requirement.

Carb & Fat Intake

Balance carbs and fat for your goals.

Macro Calculator

Get your ideal macronutrient split.

Water Intake

How much water you should drink daily.

Keto Calculator

Custom keto macros for your goals.

PREGNANCY & PARENTING

Pregnancy & Parenting Calculators

Tools built for parents-to-be and new parents.

Pregnancy & Parenting Hub

Tools for parents-to-be and new parents.

GENERAL HEALTH

General Health Calculators

8 tools to monitor heart health, sleep, and everyday wellness.

Blood Pressure

Check if your BP is in a healthy range.

Heart Rate Zone

Find your optimal training heart rate.

Cholesterol Ratio

Assess heart health via cholesterol ratio.

Diabetes Risk

Estimate type 2 diabetes risk factors.

Kidney Function

Estimate eGFR kidney performance.

Alcohol Unit

Track alcohol intake and stay within limits.

Sleep Calculator

Plan ideal sleep and wake-up times.

Age Calculator

Exact age in years, months, and days.

TESTIMONIALS

Loved by Users Worldwide

See what our users are saying about their journey to better health with our tools.

The TDEE and Macro calculators are game-changers! I finally have a clear roadmap for my nutrition.
Sarah L.
Fitness Enthusiast
I love the Sleep Calculator. It helps me optimize my rest even with a hectic schedule.
Mark R.
Busy Professional
The Pregnancy & Parenting hub has been a lifesaver. Highly recommended for all parents!
Jessica P.
New Mom
The Heart Rate Zone and TDEE calculators changed how I structure my training weeks.
David K.
Amateur Athlete
I recommend the Macro Calculator to all my clients. Results line up with manual calculations.
Priya N.
Nutrition Coach
Lost 18 lbs using the Daily Calorie and Water Intake calculators to stay on track.
Tom W.
Weight Loss Journey

FAQ

Frequently Asked Questions

Answers to common questions about our calculators and how to use them.

Yes, every calculator on Health Calculators is completely free, with no sign-up or subscription required.
Our calculators use widely accepted formulas from health and fitness research (e.g. Mifflin-St Jeor for BMR, WHO ranges for BMI). They provide reliable estimates, but individual results can vary, so always consult a healthcare professional for medical decisions.
No account is needed. Just open any calculator, enter your details, and get instant results.
If you are new to tracking your health, the BMI Calculator and TDEE Calculator are great starting points, followed by the Macro Calculator to plan your nutrition.
Calculations run entirely in your browser. We do not store or share the personal health details you enter into a calculator.
Yes, every calculator is fully responsive and works smoothly on phones, tablets, and desktops.

Ready to take control of your health?

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