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Free Online Calculators

From figuring out how much house you can afford to splitting a restaurant bill, the right calculator saves time and prevents mistakes. Our collection covers the calculations people actually need day-to-day: mortgage payments, loan EMIs, BMI, tip splits, percentage changes, VAT, date differences, unit conversions, and more.

Every calculator updates results as you type, works on mobile, and runs 100% in your browser — no account, no ads obscuring the inputs, no waiting. All 16 calculators below are completely free.

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Age Calculator

Calculate exact age in years, months, days, hours and minutes from a birth date.

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BMI Calculator

Calculate Body Mass Index with metric or imperial units and see your category.

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Percentage Calculator

Six ways to calculate percentages, increases, decreases and differences.

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Unit Converter

Convert length, weight, temperature, area, volume, speed, time and data.

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Read Time Estimator

Paste any text and instantly see reading time, speaking time and readability.

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Number Base Converter

Convert between binary, octal, decimal, hexadecimal and any custom base.

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Hours to Days

Convert hours to days with configurable decimal precision and optional "days" suffix.

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Time to Military Time

12-hour or 24-hour clock to military format with optional seconds, colons and "hours" suffix.

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Loan / EMI Calculator

Monthly instalment, total interest and a yearly amortization table for any loan.

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Mortgage Calculator

Full monthly payment — principal & interest plus tax, insurance and HOA.

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Tip Calculator

Calculate the tip and split the bill between any number of people, with rounding.

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Discount Calculator

Sale price and savings from a percentage discount, including a stacked second discount.

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VAT / Sales Tax Calculator

Add or remove VAT / GST / sales tax at any rate. See net, tax and gross.

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Date Difference Calculator

Exact years / months / days between two dates, plus total days, weeks and weekdays.

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Countdown Timer

Live countdown of days, hours, minutes and seconds to any date — deadlines, launches, new year.

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Timer / Stopwatch

Stopwatch, countdown and Pomodoro timer all in one. Lap times, alarm chime and auto work/break cycles.

Frequently Asked Questions

Are the calculator results accurate? expand_more

Yes. All calculators use standard mathematical formulas. Financial calculators (loan, mortgage, tip, VAT) use the same formulas as banking software. Always verify critical financial decisions with a qualified professional.

How is the mortgage monthly payment calculated? expand_more

The monthly payment is calculated using the standard amortization formula: M = P × r(1+r)^n / ((1+r)^n − 1), where P is the loan principal, r is the monthly interest rate, and n is the number of payments. Property tax, insurance, and HOA are added on top.

What BMI range is considered healthy? expand_more

According to the WHO, a BMI of 18.5–24.9 is considered healthy weight, 25–29.9 is overweight, and 30 or above is obese. The BMI Calculator also shows your healthy weight range for your height.

Do the calculators work on mobile? expand_more

Yes. All calculators are fully responsive and work on mobile browsers. Results update as you type, with no need to press a calculate button.