Free Online Calculators
Simple, accurate tools for finance, health, math, and everyday life. No sign-ups, no clutter, just calculators that work.
Built for students, homeowners, investors, travelers, and anyone who needs a quick answer.
All Calculators
48 free tools across 4 categories.
💰 Financial Calculators
View allTip Calculator
Quickly calculate the perfect tip amount for any bill.
Loan Calculator
Estimate monthly payments and total interest for any loan.
Mortgage Calculator
Calculate monthly mortgage payments including taxes and insurance.
Compound Interest Calculator
See how your money grows with compound interest over time.
Currency Converter
Convert between world currencies using live exchange rates.
Discount Calculator
Calculate sale prices and how much you save with any discount.
Sales Tax Calculator
Add or remove sales tax from any purchase amount.
Inflation Calculator
See how inflation erodes purchasing power over time.
Retirement Calculator
Project your retirement savings growth and estimate monthly income in retirement.
💪 Health & Fitness
View allBMI Calculator
Calculate your Body Mass Index and understand what it means.
BMR Calculator
Find your Basal Metabolic Rate. Calories burned at rest.
Calorie Calculator
Estimate daily calorie needs for weight maintenance, loss, or gain.
Body Fat Calculator
Estimate body fat percentage using simple measurements.
Due Date Calculator
Estimate pregnancy due date based on last menstrual period.
Ovulation Calculator
Estimate your ovulation date and fertile window based on your cycle.
Sleep Calculator
Find the best bedtime or wake time based on sleep cycles.
🔢 Math & Conversions
View allPercentage Calculator
Calculate percentages, percentage changes, and more.
Fraction Calculator
Add, subtract, multiply, and divide fractions.
Ratio Calculator
Simplify ratios and find missing values in proportions.
Square Root Calculator
Calculate square roots and nth roots of any number.
Binary Calculator
Convert between decimal, binary, and octal number systems.
Hex Calculator
Convert between hexadecimal, decimal, and binary number systems.
Roman Numeral Converter
Convert between Roman numerals and decimal numbers (1-3999).
Prime Numbers Calculator
Check if a number is prime, find prime factors, and list primes up to any value.
Factorial Calculator
Calculate the factorial of any number up to 170.
Combinations and Permutations
Calculate combinations (nCr) and permutations (nPr) for any values.
Significant Figures Calculator
Count significant figures and round numbers to a specified number of sig figs.
Scientific Notation Converter
Convert between decimal and scientific notation instantly.
Fuel Cost Calculator
Calculate trip fuel costs based on distance, efficiency, and fuel price.
Electricity Calculator
Calculate electricity costs for any appliance based on power, usage, and rate.
Scientific Calculator
Perform advanced math with trigonometric, logarithmic, and exponential functions.
Unit Converter
Convert between units of length, weight, volume, temperature, and more.
Time Converter
Convert between seconds, minutes, hours, days, weeks, and more.
Speed Converter
Convert between mph, km/h, knots, and mach speed.
🛠️ Other Tools
View allAge Calculator
Calculate your exact age in years, months, and days.
Date Difference Calculator
Find the exact number of days between two dates.
GPA Calculator
Calculate your grade point average across multiple courses.
Password Strength Checker
Check how strong your password is against common attacks.
Random Number Generator
Generate random numbers within any range.
Stopwatch
A simple accurate stopwatch for timing anything.
Countdown Timer
Set a countdown timer for any number of minutes.
Timer
Set a precise timer with hours minutes and seconds.
Time Zone Converter
Convert times between different time zones.
World Clock
View current time in major cities worldwide.
ETA Calculator
Calculate travel time and estimated arrival.
Tip Split Calculator
Split a bill evenly including tip.
Color Converter
Convert colors between HEX RGB and HSL.
Character and Word Counter
Count characters words sentences and more.