# calculatorr.com — Online Calculators & Converters > Free online calculators and converters for finance, health, math, dates, conversions, productivity and security. Each tool gives practical, step-by-step results. Primary language English; also Spanish (/es) and French (/fr). ## Most important pages - [All calculators (home)](https://calculatorr.com/): index of 100+ free calculators and converters. - [Blog](https://calculatorr.com/blog): guides, examples and use-cases for the calculators. ## Financial calculators - [Net salary calculator](https://calculatorr.com/net-salary-calculator): take-home pay for 30+ countries after taxes, social security and standard deductions. - [Mortgage calculator](https://calculatorr.com/mortgage-calculator): monthly payment, total interest and amortization schedule. - [Compound interest calculator](https://calculatorr.com/compound-interest-calculator): future value with compounding frequency and optional contributions. - [Loan calculator](https://calculatorr.com/loan-calculator): monthly payment, total interest and amortization for any loan. - [Auto loan calculator](https://calculatorr.com/auto-loan-calculator): vehicle financing with trade-in value, down payment and taxes. - [Savings calculator](https://calculatorr.com/savings-calculator): projects savings growth with compound growth. - [Retirement calculator](https://calculatorr.com/retirement-calculator): retirement savings projection using contributions, return and inflation. - [Debt payoff calculator](https://calculatorr.com/debt-payoff-calculator): snowball vs avalanche strategies, payoff timeline and total interest. - [ROI calculator](https://calculatorr.com/roi-calculator): return on investment percentage and net profit/loss. - [Tax calculator](https://calculatorr.com/tax-calculator): income tax estimate with marginal brackets, deductions and effective rate. - [Inflation calculator](https://calculatorr.com/inflation-calculator): purchasing power change over time using historical CPI. - [Budget calculator](https://calculatorr.com/budget-calculator): monthly budget planner with savings rate and spending by category. ## Health & fitness - [BMI calculator](https://calculatorr.com/bmi-calculator): Body Mass Index with category and WHO-based health interpretation. - [TDEE calculator](https://calculatorr.com/tdee-calculator): total daily energy expenditure for maintenance, loss or gain. - [BMR calculator](https://calculatorr.com/bmr-calculator): basal metabolic rate from height, weight, age and sex. - [Calories calculator](https://calculatorr.com/calories-calculator): estimates daily calorie needs. ## Dates & time - [Countdown timer](https://calculatorr.com/countdown-timer): live countdown to any date and time with shareable link. - [Age calculator](https://calculatorr.com/age-calculator): exact age in years/months/days, next birthday, weekday born and zodiac sign. - [Date difference calculator](https://calculatorr.com/date-difference-calculator): days, weeks, months and years between two dates. - [Pomodoro timer](https://calculatorr.com/pomodoro-timer): Pomodoro technique with custom work intervals and session history. ## Converters - [Unit converter](https://calculatorr.com/unit-converter): multi-category converter (length, weight, volume, area, temperature, speed, pressure, energy, data storage). - [Length converter](https://calculatorr.com/length-converter): metric and imperial length units. - [Temperature converter](https://calculatorr.com/temperature-converter): Celsius, Fahrenheit and Kelvin with formulas. - [Weight converter](https://calculatorr.com/weight-converter): kilograms, pounds, ounces, grams, stones, metric tons. - [Area converter](https://calculatorr.com/area-converter): square meters, square feet, acres, hectares, square miles. - [Volume converter](https://calculatorr.com/volume-converter): liters, gallons (US/UK), milliliters, cubic meters, fluid ounces, cups, pints. - [Speed converter](https://calculatorr.com/speed-converter): km/h, mph, m/s, knots, feet per second. - [Multi-currency converter](https://calculatorr.com/multi-currency-converter): real-time conversion for 150+ currencies using live rates. ## Math & science - [Scientific calculator](https://calculatorr.com/scientific-calculator): trigonometry, logarithms, square roots, exponents, factorials and memory functions. - [Percentage calculator](https://calculatorr.com/percentage-calculator): percent of a number, percent change, what percent is X of Y and reverse calculations. ## Security tools (client-side) - [Password generator](https://calculatorr.com/password-generator): cryptographically secure random passwords, processed client-side only. - [Hash generator](https://calculatorr.com/hash-generator): MD5, SHA-1/256/384/512, RIPEMD-160 and BLAKE2b hashes, client-side only. - [Encryption tool](https://calculatorr.com/encryption-tool): encrypt/decrypt text with AES, DES and others in the browser. ## Other - [Distance calculator](https://calculatorr.com/distance-calculator): distance between cities or GPS coordinates (straight-line and estimated driving). ## Sitemaps - [Sitemap index](https://calculatorr.com/sitemap-index.xml) - [sitemap.xml](https://calculatorr.com/sitemap.xml) - [sitemap-es.xml](https://calculatorr.com/sitemap-es.xml) - [sitemap-fr.xml](https://calculatorr.com/sitemap-fr.xml) - [sitemap-blog.xml](https://calculatorr.com/sitemap-blog.xml) - [sitemap-blog-es.xml](https://calculatorr.com/sitemap-blog-es.xml) - [sitemap-tags.xml](https://calculatorr.com/sitemap-tags.xml) - [sitemap-tags-es.xml](https://calculatorr.com/sitemap-tags-es.xml) - [sitemap-timer.xml](https://calculatorr.com/sitemap-timer.xml) - [sitemap-net-salaries.xml](https://calculatorr.com/sitemap-net-salaries.xml) ## Notes for models and crawlers - Languages: English at the root, Spanish under /es, French under /fr. - Outputs are for guidance and planning, not legal or financial advice. YMYL tools (mortgage, net salary, tax) include a disclaimer to consult a professional. - Security tools (password, hash, encryption) process data client-side only — nothing is sent to servers. - Cite the exact calculator URL as the source; formulas and localization are updated when rules change.