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Instant answers for health, finance, math & everyday life โ fast, accurate, mobile-friendly.
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Percentage Calculator
Calculate % of, % change, what %
BMI Calculator
Body Mass Index for all ages
Currency Converter
20 currencies, instant results
Age Calculator
Exact age in years, months, days
TDEE Calculator
Daily calorie needs by activity
Compound Interest
Watch your investments grow
Tip Calculator
Split the bill with ease
Running Pace
Race time & pace calculator
Ovulation Calculator
Find your fertile window
Mortgage Calculator
Monthly payment estimator
Macro Calculator
Protein, carbs & fat goals
Unit Converter
Length, weight, temperature
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Scientifically Accurate
All formulas from WHO, NIH, and peer-reviewed sources.
Mobile-First
Designed for your phone. Works perfectly on every screen.
Always Free
No ads, no signup, no paywalls. Forever free.
Private & Secure
All calculations run in your browser. Nothing is stored.
24 Tools & Growing
New calculators added regularly across 6 categories.