Health Tools
BMI, calorie, sleep, hydration — track your health basics in a private, browser-only way.
Overview
Health calculators are some of the most-used utilities on the internet — but the privacy story matters more here than elsewhere. Body data, sleep patterns, fertility tracking — none of this should be uploaded to ad-funded servers. Everything in this category runs entirely in your browser, with optional localStorage persistence (only on your device).
Common Use Cases
- →Track BMI, body fat percentage, and ideal weight ranges.
- →Calculate daily calorie needs (TDEE) and macros for goals.
- →Optimize sleep schedules around 90-minute REM cycles.
- →Plan hydration based on weight, activity, and climate.
Featured Tools
- BMI Calculator
Calculate Body Mass Index (BMI) for health tracking.
- TDEE Calculator
Calculate your Total Daily Energy Expenditure for weight goals.
- Sleep Calculator
Calculate optimal bedtime and wake up times for better rest.
- Water Intake Calculator
Calculate your daily water intake needs for optimal hydration.
Frequently Asked Questions
Are these tools a substitute for a doctor?
No — they're screening and planning tools. BMI flags categories for follow-up; calorie calculators estimate needs but real metabolism varies ±15%. Use as a starting point and always consult a healthcare professional for clinical decisions.
Is my fertility/period data private?
Yes — period and ovulation trackers store data only in your browser's localStorage. Nothing is sent to a server. Read more about our privacy stance on the About page.
Why does TDEE feel high or low?
Mifflin-St Jeor (the standard formula) is ±10% accurate for most people. Athletes with high muscle mass or unusually low body fat may need the Katch-McArdle formula instead. Track 2-3 weeks of food and weight to dial in your personal multiplier.
Sleep Calculator
Calculate optimal bedtime and wake up times for better rest.
Ovulation Calculator
Predict your most fertile days and ovulation window.
Pregnancy Due Date Calculator
Calculate your estimated pregnancy due date and track trimesters.
BMR Calculator
Calculate your Basal Metabolic Rate for nutrition planning.
Protein Calculator
Calculate your daily protein needs based on weight and activity level.
Water Intake Tracker
Track your daily water consumption for health.
Calorie Calculator
Calculate your optimal daily calorie intake and macro split based on your goals.
Period Tracker
Simple cycle tracking for health and wellness.
BMI Calculator
Calculate Body Mass Index (BMI) for health tracking.
TDEE Calculator
Calculate your Total Daily Energy Expenditure for weight goals.
Ideal Weight Calculator
Find your ideal body weight based on height and gender.
Body Fat Calculator
Calculate body fat percentage using the US Navy method.
BMR Calculator
Calculate your Basal Metabolic Rate for nutrition planning.
TDEE Calculator
Calculate your Total Daily Energy Expenditure for weight goals.
Water Intake Calculator
Calculate your daily water intake needs for optimal hydration.
Protein Calculator
Calculate your daily protein needs based on weight and activity level.
Pregnancy Due Date Calculator
Calculate your estimated pregnancy due date and track trimesters.
Ovulation Calculator
Predict your most fertile days and ovulation window.
Age Calculator
Calculate your exact age in years, months, and days.
Date Difference Calculator
Calculate exact days, months, and years between two dates.