All Free Online Tools
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20 tools
Percentage Calculator
Work out percentages, increases, decreases, and changes.
Age Calculator
Calculate exact age in years, months, days, and more.
BMI Calculator
Calculate body mass index from height and weight.
Loan / EMI Calculator
Estimate monthly payments, total interest, and total cost.
Compound Interest Calculator
Project savings and investments with compounding.
Simple Interest Calculator
Calculate simple interest on a principal amount.
Discount Calculator
Find the sale price and money saved from a discount.
Tip Calculator
Calculate tips and split the bill between people.
Date Difference Calculator
Find the number of days between two dates.
Unit Converter
Convert length, weight, temperature, area, and volume units.
Average Calculator
Find the mean, median, and range of a set of numbers.
Standard Deviation Calculator
Compute population and sample standard deviation.
Sales Tax / VAT Calculator
Add or remove sales tax and VAT from any amount.
ROI Calculator
Calculate return on investment and annualized ROI.
Profit Margin Calculator
Calculate gross margin, markup, and profit.
GPA Calculator
Calculate weighted GPA from course grades and credits.
Quadratic Equation Calculator
Solve ax² + bx + c = 0 including complex roots.
GCF & LCM Calculator
Find the greatest common factor and least common multiple.
Prime Number Checker
Test whether a number is prime and factor it.
Scientific Calculator
Evaluate expressions with trigonometry, logs, and powers.