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Sitemap: https://calculatodo.com/sitemap.xml

# Calculatodo

> Free online calculators for health, finance, math, geometry, calendar, statistics, and more. All calculations run client-side with instant results. Available in 28 languages.

Calculatodo.com provides free, ad-supported online calculators. Each calculator includes an interactive tool and educational content explaining the formulas, methodology, and practical applications. No registration required.

## Health Calculators

- [BMI Calculator](https://calculatodo.com/en/calculate-body-mass-index-bmi): Calculate Body Mass Index from height and weight. Includes BMI classification table (underweight, normal, overweight, obese) and health risk information.
- [Body Fat Calculator](https://calculatodo.com/en/calculate-body-fat): Estimate body fat percentage using the U.S. Navy method with neck, waist, and hip measurements.
- [Basal Metabolic Rate Calculator](https://calculatodo.com/en/calculate-basal-metabolic-rate-bmr): Calculate BMR using the Mifflin-St Jeor equation to estimate daily calorie needs at rest.
- [PaFi Ratio Calculator](https://calculatodo.com/en/pf-ratio-calculator): Calculate the PaO2/FiO2 ratio used in medicine to assess oxygenation and classify respiratory distress (ARDS).

## Finance Calculators

- [Compound Interest Calculator](https://calculatodo.com/en/compound-interest-calculator): Calculate compound interest with customizable principal, rate, time period, and compounding frequency. Includes growth table.
- [Simple Interest Calculator](https://calculatodo.com/en/simple-interest-calculator): Calculate simple interest given principal, annual rate, and time period.
- [NPV and IRR Calculator](https://calculatodo.com/en/net-present-value-npv-and-irr-calculator): Calculate Net Present Value (NPV) and Internal Rate of Return (IRR) for investment cash flows.
- [Boleta de Honorarios Calculator](https://calculatodo.com/calcular-boleta-de-honorarios): (Spanish only) Calculate Chilean freelancer invoice withholding tax based on current UF value and retention rate.
- [IVA Calculator](https://calculatodo.com/calculadora-iva): (Spanish only) Calculate Chilean Value Added Tax (IVA) at 19%.

## Math Calculators

- [Weighted Average Calculator](https://calculatodo.com/en/weighted-average-calculator): Calculate weighted average / weighted GPA with customizable values and weights.
- [Percentage Calculator](https://calculatodo.com/en/calculate-percentage): Calculate percentages: what is X% of Y, X is what % of Y, and percentage change between two values.
- [Rule of Three Calculator](https://calculatodo.com/en/calculate-rule-of-three): Solve direct and inverse proportions using the rule of three (cross-multiplication).
- [Binary Number Calculator](https://calculatodo.com/en/binary-number-calculator): Convert between binary and decimal. Perform addition, subtraction, multiplication, and division with binary numbers.
- [Hexadecimal Number Calculator](https://calculatodo.com/en/hexadecimal-number-calculator): Convert between hexadecimal and decimal. Perform arithmetic operations with hex numbers.
- [LCM Calculator](https://calculatodo.com/en/calculate-least-common-multiple-lcm): Calculate the Least Common Multiple (LCM) of two or more numbers.
- [Fraction Calculator](https://calculatodo.com/en/fraction-calculator): Add, subtract, multiply, and divide fractions. Simplify results automatically.

## Geometry Calculators

- [Circle Area Calculator](https://calculatodo.com/en/calculate-area/circle): Calculate the area and circumference of a circle given its radius. Formula: A = pi * r^2.
- [Square Area Calculator](https://calculatodo.com/en/calculate-area/square): Calculate the area and perimeter of a square given its side length. Formula: A = s^2.
- [Rectangle Area Calculator](https://calculatodo.com/en/calculate-area/rectangle): Calculate the area and perimeter of a rectangle given width and height. Formula: A = w * h.
- [Cylinder Surface Area Calculator](https://calculatodo.com/en/calculate-area/cylinder): Calculate the surface area and volume of a cylinder given radius and height.
- [Cube Surface Area Calculator](https://calculatodo.com/en/calculate-area/cube): Calculate the surface area and volume of a cube given its edge length.
- [Sphere Surface Area Calculator](https://calculatodo.com/en/calculate-area/sphere): Calculate the surface area and volume of a sphere given its radius. Formula: A = 4 * pi * r^2.
- [Distance Between Points Calculator](https://calculatodo.com/en/calculate-distance-between-points): Calculate the Euclidean distance between two points in a 2D plane using the distance formula.
- [Hypotenuse Calculator](https://calculatodo.com/en/calculate-hypotenuse): Calculate the hypotenuse of a right triangle using the Pythagorean theorem: c = sqrt(a^2 + b^2).

## Calendar & Time Calculators

- [Age Calculator](https://calculatodo.com/en/chronological-age-calculator): Calculate exact chronological age in years, months, and days from a birth date.
- [Days Between Dates Counter](https://calculatodo.com/en/count-days-between-dates): Count the exact number of days, weeks, and months between any two dates.
- [Add or Subtract Days to a Date](https://calculatodo.com/en/add-subtract-days-to-date): Add or subtract days, weeks, or months from a given date to find the resulting date.
- [Hours and Minutes Calculator](https://calculatodo.com/en/hours-and-minutes-calculator): Add and subtract hours and minutes. Useful for time tracking and scheduling.
- [Overtime Hours Calculator](https://calculatodo.com/en/worked-hours-and-overtime-calculator): Calculate worked hours and overtime pay based on clock-in/clock-out times and hourly rate.
- [Legal Holiday Calculator](https://calculatodo.com/calcular-dias-vacaciones-feriado-legal): (Spanish only) Calculate Chilean legal vacation days based on years of service.

## Statistics Calculators

- [Mean, Median, and Mode Calculator](https://calculatodo.com/en/calculate-mean-median-mode-statistics): Calculate mean (average), median (middle value), and mode (most frequent value) from a dataset.
- [Variance Calculator](https://calculatodo.com/en/calculate-variance): Calculate population and sample variance from a set of numbers.
- [Standard Deviation Calculator](https://calculatodo.com/en/calculate-standard-deviation): Calculate population and sample standard deviation from a dataset.

## Other Tools

- [Gas Trip Cost Calculator](https://calculatodo.com/en/calculate-gasoline-expense-trip): Estimate fuel cost for a trip based on distance, fuel efficiency, and gas price.
- [Word and Character Counter](https://calculatodo.com/en/word-character-counter): Count words, characters, sentences, and paragraphs in any text. Useful for writing and SEO.
- [Roman Numeral Converter](https://calculatodo.com/en/roman-numerals-decimal-arabic-converter): Convert between Roman numerals and decimal (Arabic) numbers in both directions.
- [CPS Test - Clicks Per Second](https://calculatodo.com/en/clicks-per-second-cps-test): Test your clicking speed. Measure clicks per second (CPS) over customizable time intervals.
- [Grade Scale Generator](https://calculatodo.com/en/generate-grade-scale-score-table): Generate a grading scale table with customizable score ranges and passing thresholds.
- [Random Number Generator](https://calculatodo.com/en/random-number-generator): Generate random numbers within a custom range. Supports generating multiple numbers at once.

## Supported Languages

Available in 28 languages: Spanish (default), English, Portuguese, French, German, Italian, Czech, Danish, Finnish, Norwegian, Dutch, Polish, Swedish, Turkish, Arabic, Bulgarian, Bengali, Hindi, Hungarian, Indonesian, Japanese, Romanian, Russian, Thai, Ukrainian, Urdu, Vietnamese, and Chinese.

Each language has fully localized URLs, content, and interface. Language-specific URLs follow the pattern: `https://calculatodo.com/{lang-code}/...`

## Optional

- [Privacy Policy (EN)](https://calculatodo.com/en/privacy-policy)
- [Sitemap](https://calculatodo.com/sitemap.xml)