Math calculators built for clarity.
Percentages, fractions, ratios, GPA, statistics, random numbers, and more — each tool gives you a clean answer with the working shown. No clutter, no popups, no guessing.
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Start with our most-used math tools
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Pick the kind of math you need
Every tool grouped by what you're actually trying to do — from quick percentages to GPA planning.
Percentages & ratios
Everyday percent and ratio math — for shopping, school, work, and quick sanity checks.
Fractions & decimals
Convert between fractions and decimals or do arithmetic with mixed numbers.
General math & statistics
A full scientific keypad plus the stats tools you reach for most often.
School & grades
GPA, course grades, and what-if scenarios for the next test.
Time & date math
Age, date differences, hours worked — handled with full calendar awareness.
Age Calculator
Exact age in years, months, days, hours.
Time & Date →Date Difference
Days between any two dates.
Time & Date →Date Calculator
Add or subtract days, weeks, months from a date.
Time & Date →Time Calculator
Add, subtract, and convert hours, minutes, seconds.
Time & Date →Hours Calculator
Hours worked between two times — payroll-friendly.
Time & Date →Number utilities
Quick-use generators and converters that play well with math.
Learn
Short, plain-English math explainers
Quick refreshers paired with the calculators above — written to teach the idea, not just give an answer.
Percent of, percent change, percent difference
Three percent calculations that look similar but answer different questions — with examples.
Open Percentage CalculatorFractions without the headache
A clean refresher on adding, subtracting, and converting fractions to decimals.
Open Fraction CalculatorWhat standard deviation actually tells you
How spread, variance, and standard deviation describe a dataset in plain English.
Open Standard DeviationHow GPA is calculated
Weighted vs. unweighted GPA, credit hours, and how to plan for a target.
Open GPA CalculatorInstant & accurate
Calculations run in your browser the moment you type — no waiting, no round-trips.
The working, shown
Each result is paired with the formula and a short explanation, so you learn while you use it.
Private by default
Numbers stay on your device. We don't store, sell, or upload anything you type.