Everyday
Percentage Calculator
Find percentages, increases, decreases, and what one number is of another.
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Fast, clear tools for numbers that matter
Seven calculators cover everyday percentages, age and elapsed time, molarity, compound interest, algebra, and GPA. Each tool shows the result first and keeps the working visible.
Browse calculators
Percentages, dates, science, finance, math, and GPA.
Calculators
Browse all seven calculators by category, or search by name.
Date & Time
Age Calculator
Determine exact age from a birth date, or years between two dates.
Open calculatorDate & Time
Time Duration Calculator
Measure elapsed time between two clock times or datetimes in clear units.
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Molarity Calculator
Relate moles of solute, solution volume, and molar concentration (mol/L).
Open calculatorFinance
Compound Interest Calculator
Project growth with compounding periods, interest rate, and time horizon.
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Math Solver
Simplify expressions, solve linear and quadratic equations, factor, and work with fractions and trigonometry.
Open calculatorAcademics
GPA Calculator
Calculate semester GPA, cumulative GPA, weighted GPA, and the average needed to reach a target GPA.
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