Free Online Calculators
for Everything
Calculate age, mortgage payments, compound interest, countdowns, and much more. Fast, accurate, and easy to use.
CalcHub provides a growing collection of carefully designed calculators for everyday financial, date, time, and personal calculations. All calculators are 100% free, require no sign-up, perform calculations in your browser (your data stays private), and are designed for accuracy and ease of use. Whether you're calculating your exact age, mortgage affordability, investment growth, or the cost of your daily coffee habit, CalcHub has the right tool.
✓ All calculators are developed with clear methodologies, worked examples, and detailed explanations so you understand both HOW they work and WHY the results matter.
Popular Calculators
Day of the Week Calculator
Find out what day of the week any date falls on. Perfect for birthdays, historical events, or planning future dates.
Days Between Dates Calculator
Calculate the exact number of days between any two dates. Great for planning events, tracking deadlines, or counting down.
Days Until Christmas
Count down to Christmas Day with a live timer showing days, hours, minutes, and seconds until December 25th.
Days Until Thanksgiving
Count down to Thanksgiving with a live timer. Find out exactly when Thanksgiving is this year.
Days Until New Year's Day
Count down to New Year's Day with a live timer. See how much time is left in the year.
Age Calculator
Calculate your exact age in years, months, days, hours, minutes, and seconds. Discover how many days you've been alive.
Birthday Countdown
Count down to your next birthday with a live timer. See exactly how many days, hours, minutes, and seconds until your special day.
Mortgage Calculator – Estimate Your Monthly Payment
Use our free mortgage calculator to estimate your monthly payment, including principal, interest, property taxes, homeowners insurance, PMI, and HOA fees. Enter your loan amount, interest rate, and loan term to see your total monthly housing payment and lifetime loan cost.
How Much House Can I Afford? – Home Affordability Calculator
Estimate how much house you can afford based on your income, debts, down payment, and interest rate using the 28/36 guideline. This is an estimator for planning purposes only and does not determine mortgage eligibility.
Rent vs Buy Calculator
Compare renting vs. buying a home over your desired timeframe. Account for mortgage, taxes, insurance, maintenance, rent increases, home appreciation, and investment returns. Transparent assumptions, no hidden costs.
Compound Interest Calculator – Investment Growth
Calculate compound interest and investment growth with our free calculator. Enter your starting balance, monthly contributions, interest rate, and time period to see how your investments grow. Includes yearly breakdown and comparison of compound vs. simple interest.
Retirement Calculator – Plan Your Retirement
Calculate your retirement savings needs based on your current age, savings, contributions, and expected investment returns. This calculator projects your retirement balance and estimates retirement income using the 4% rule.
Hourly to Salary Calculator
Convert hourly wages to annual salary and vice versa. See weekly, biweekly, and monthly earnings.
Tip Calculator
Calculate tips quickly and easily. Split bills among multiple people and see total with tip.
The End of the World Calculator
A humorous calculator that generates a fictional "end of the world" date based on your answers to silly questions. For entertainment only!
Percentage Calculator
Calculate percentages for all common scenarios. Find what percent one number is of another, calculate percentage increases and decreases (like salary raises or price markups), determine the original amount when you know the percentage, and solve percentage word problems. Works for grades, finances, statistics, tips, and everyday math.
Random Choice Generator
Need help making a decision? Use our random choice generator to pick one or multiple options from your list. Perfect for choosing dinner, selecting team members, or breaking ties. Add your own options and let randomness decide!
Trending Tools
Days Left in the Year
Find out how many days, weeks, and weekends are left in the current year. Track your progress through the year.
Days Until Christmas
Count down to Christmas Day with a live timer showing days, hours, minutes, and seconds until December 25th.
Age Calculator
Calculate your exact age in years, months, days, hours, minutes, and seconds. Discover how many days you've been alive.
How Many Days Have I Been Alive?
Find out exactly how many days, hours, and minutes you've been alive. Discover fascinating life statistics.
What Generation Am I?
Find out which generation you belong to based on your birth year. Learn about Gen Z, Millennials, Gen X, and more.
Credit Card Payoff Calculator – How Long to Eliminate Debt
Calculate how long it will take to pay off credit card debt and how much interest you will pay. Enter your current balance, interest rate, and monthly payment to see your estimated payoff timeline and total interest cost.
When Will I Become a Millionaire?
Estimate when your savings and investments will reach $1,000,000 based on your current savings, monthly contributions, and expected investment returns.
How Many Heartbeats Have I Had?
Estimate how many times your heart has beaten since you were born. A fascinating life statistic.
How Many Pizzas Have I Eaten?
Estimate how many pizzas you've eaten in your lifetime based on your age and eating habits.
How Much Coffee Have I Drunk?
Calculate how much coffee you've consumed in your lifetime. See cups, gallons, and cost.
The End of the World Calculator
A humorous calculator that generates a fictional "end of the world" date based on your answers to silly questions. For entertainment only!
Custom Spinner – Decision Wheel
Create your own decision wheel with custom options. Perfect for making choices, picking team members, choosing meals, or any decision-making situation. Add, edit, or remove options, then spin the wheel for a random selection.
Money & Finance Calculators
Mortgage Calculator – Estimate Your Monthly Payment
Use our free mortgage calculator to estimate your monthly payment, including principal, interest, property taxes, homeowners insurance, PMI, and HOA fees. Enter your loan amount, interest rate, and loan term to see your total monthly housing payment and lifetime loan cost.
How Much House Can I Afford? – Home Affordability Calculator
Estimate how much house you can afford based on your income, debts, down payment, and interest rate using the 28/36 guideline. This is an estimator for planning purposes only and does not determine mortgage eligibility.
Mortgage Payoff Calculator
Calculate how quickly you can pay off your mortgage with extra payments. See total interest savings.
Rent vs Buy Calculator
Compare renting vs. buying a home over your desired timeframe. Account for mortgage, taxes, insurance, maintenance, rent increases, home appreciation, and investment returns. Transparent assumptions, no hidden costs.
Compound Interest Calculator – Investment Growth
Calculate compound interest and investment growth with our free calculator. Enter your starting balance, monthly contributions, interest rate, and time period to see how your investments grow. Includes yearly breakdown and comparison of compound vs. simple interest.
Loan Payment Calculator
Calculate monthly loan payments for any type of loan. See total interest and payoff timeline.
Fun & Viral Calculators
How Many Pizzas Have I Eaten?
Estimate how many pizzas you've eaten in your lifetime based on your age and eating habits.
How Much Coffee Have I Drunk?
Calculate how much coffee you've consumed in your lifetime. See cups, gallons, and cost.
How Much Money Have I Spent on Coffee?
Calculate how much money you've spent on coffee in your lifetime. You might be surprised!
The End of the World Calculator
A humorous calculator that generates a fictional "end of the world" date based on your answers to silly questions. For entertainment only!
Miller's Planet Time Calculator
Experience extreme time dilation with this Interstellar-inspired calculator. Convert between Miller's Planet time and Earth time using the movie's famous 1-hour-to-7-years scenario. Explore how gravitational time dilation works near Gargantua.
Murphy's Law Calculator
Calculate the probability of at least one failure across multiple opportunities. An educational probability and entertainment tool.