Calculators

Convert between Celsius, Fahrenheit, and Kelvin online. Free temperature converter with instant results and conversion formulas.

Convert between meters, feet, inches, miles, and more length units online. Free length converter with instant accurate results.

Convert between kilograms, pounds, ounces, grams, and more weight units online. Free mass converter with instant calculations.

Convert between square meters, square feet, acres, hectares, and more area units online. Free area converter with precision.

Convert between liters, gallons, cups, milliliters, and more volume units online. Free volume converter with instant results.

Convert between bytes, KB, MB, GB, and TB online. Free data size converter for storage and bandwidth calculations with precision.

Convert between Roman and Arabic numerals online instantly. Free Roman numeral converter with validation and bidirectional support.

Convert between various measurement units online including length, weight, volume, and temperature. Free universal unit converter.

Convert Unix timestamps to human-readable dates and vice versa online. Free timestamp converter with timezone support and formatting.

Calculate date differences and add or subtract days, months, and years online. Free date calculator with weekday and holiday support.

Calculate the exact difference between two dates in days, weeks, months, and years online. Free date difference calculator tool.

Calculate percentages online with increase, decrease, and ratio modes. Free percentage calculator for discounts, tips, and math.

Convert between pixels and rem/em units online for responsive CSS. Free PX to REM converter with custom base font size support.

Convert between binary, decimal, hexadecimal, and octal number systems online. Free number base converter for programmers and students.

Calculate aspect ratios and scale dimensions proportionally online. Free aspect ratio calculator for images, video, and screen sizes.

Calculate string byte size in UTF-8, UTF-16, and other encodings online. Free byte counter for measuring text payload and storage.

Calculate loan payments, interest rates, and amortization schedules online. Free loan calculator for mortgages and personal loans.

Calculate discounts, sale prices, and savings online. Free discount calculator showing final price after percentage or dollar off deals.

Calculate the greatest common divisor and least common multiple online. Free GCD/LCM calculator with step-by-step solutions shown.

Check if a number is prime online with instant results and prime factorization. Free prime number checker for math and cryptography.

Calculate the factorial of any number online with support for large values. Free factorial calculator for math and combinatorics work.

Calculate compound interest with annual, monthly, or daily compounding online. Free investment calculator showing growth over time.

Calculate fuel costs for road trips online based on distance, gas price, and fuel efficiency. Free trip cost estimator for drivers.

Calculate sales tax amounts and total prices online. Free sales tax calculator with pre-tax and post-tax price breakdown support.

Calculate daily calorie needs based on age, weight, height, and activity level online. Free TDEE and BMR calorie calculator tool.

Calculate tips and split bills among friends online. Free tip calculator with custom tip percentages and per-person amount breakdown.

Calculate your exact age from birthdate in years, months, and days online. Free age calculator with upcoming birthday countdown.

Calculate Body Mass Index online with weight and height inputs. Free BMI calculator with health category classification and chart.

Convert oven temperatures between Fahrenheit, Celsius, and Gas Mark instantly. Free cooking temperature converter with common preset temperatures.

Convert numbers between standard notation, scientific notation, and engineering notation. Free scientific notation calculator with step-by-step conversion.

Generate Fibonacci sequences and check if a number is a Fibonacci number. Free Fibonacci calculator with custom sequence length and golden ratio.

Find the ISO week number for any date and list all dates in a given week. Free week number lookup with calendar year overview.

Find what day of the year any date falls on (1-365) and convert day numbers back to dates. Free day-of-year calculator with remaining days count.

Calculate the true cost of meetings based on attendees, hourly rates, and duration. Free meeting cost estimator to optimize your team's time.

Calculate your break-even point in units and revenue from fixed costs, variable costs, and price. Free break-even analysis tool for business planning.

Calculate your baby's exact age in years, months, weeks, and days from their birth date. Free baby age tracker with milestone timeline.

Calculate your lean body mass from weight and body fat percentage. Free LBM calculator using Boer, James, and Hume formulas.

Calculate your optimal daily creatine dosage based on body weight for loading and maintenance phases. Free creatine intake calculator for athletes.

Add and subtract multiple time durations in hours, minutes, and seconds. Free time calculator for timesheets, video editing, and project tracking.

Calculate ideal responsive font sizes based on viewport width and base size. Free font size calculator with px, rem, em conversion and WCAG compliance.

Estimate your VO2 max from run or walk test data using Cooper, Rockport, and other formulas. Free cardio fitness calculator.

Calculate how long caffeine stays in your system. Free caffeine half-life calculator with metabolism visualization and sleep impact analysis.

Create a budget using the 50/30/20 rule — 50% needs, 30% wants, 20% savings. Free budget breakdown calculator with visual charts.

Calculate gross and net rental yield on investment properties. Factor in expenses, vacancy, and management fees. Free rental ROI calculator.

Estimate jet lag recovery time and get personalized tips based on time zone difference, direction of travel, and departure time.

Find your Chinese zodiac animal and element from your birth year. Learn personality traits, compatibility, and lucky attributes.

Estimate total diaper expenses from birth through potty training. Compare brand costs and see monthly spending by age. Free baby budget tool.

Check if your dog or cat is at a healthy weight. Calculate pet body condition score and get ideal weight range by breed and size.

Add, subtract, multiply, and divide binary numbers with step-by-step solutions. Convert between binary, decimal, octal, and hex.

Calculate the moon phase for any date with visual representation. See full moon, new moon, and lunar cycle data. Free moon phase tool.

Estimate project costs by adding tasks with hours and rates. Include contingency buffer and generate cost breakdowns. Free project calculator.

Split a receipt or bill among multiple people with unequal shares, tax, and tip. Handles shared and individual items. Free bill splitter.

Calculate compound profit growth over time with reinvestment rates. Visualize growth with interactive charts. Free compound interest tool.

Calculate your biorhythm cycles based on birth date online. Free biorhythm calculator with physical, emotional, and intellectual cycle charts and daily values.

Input a number sequence and identify the pattern online. Free number pattern finder that detects arithmetic, geometric, Fibonacci, and polynomial sequences.

Make better decisions with a weighted decision matrix online. Free decision matrix tool with customizable options, criteria, weights, and automatic scoring.