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Popular Calculators

Compound Interest Calculator

Calculate how your investments grow over time with compound interest. Add regular contributions, compare compounding frequencies, and visualize your wealth building journey.

Finance

Mortgage Calculator

Calculate your monthly mortgage payment, see the full amortization schedule, and understand how much house you can afford. Free, no signup required.

Finance

Retirement Calculator

Calculate how much you need to retire, your FIRE number, and whether you are on track. See projections for your retirement savings growth over time.

Finance

Debt Payoff Calculator

Calculate how fast you can pay off your debt with extra payments. See how much interest you will save and when you will be debt-free.

Finance

Paycheck Calculator

Calculate your take-home pay after taxes and deductions. Estimate federal, state, and FICA taxes to see your actual paycheck amount.

Finance

Credit Card Payoff Calculator

Calculate how long it will take to pay off your credit card and how much interest you'll pay. See how extra payments can save you money and time.

Finance

Home Affordability Calculator

Find out how much house you can afford based on your income, debts, and down payment. Get a realistic home buying budget with monthly payment estimates.

Home & DIY

Age Calculator

Calculate your exact age in years, months, and days. Find out how old you are or will be on any date. Also shows total days lived and days until next birthday.

Date & Time

Fuel Cost Calculator

Calculate how much gas will cost for your trip. Enter distance, fuel efficiency, and gas price to estimate your fuel expenses for any journey.

Auto

Margin & Markup Calculator

Calculate profit margin and markup percentage. Convert between margin and markup, find selling price from cost, or calculate cost from selling price.

Business

Hourly to Salary Calculator

Convert hourly wage to annual salary and vice versa. See how much you make yearly, monthly, and weekly based on your hourly rate and hours worked.

Finance

Discount Calculator

Calculate the sale price after a discount and see how much you save. Works with percentage off, dollar off, and multiple discounts.

Math

Calorie Calculator

Calculate how many calories you need per day based on your age, weight, height, and activity level. Find your TDEE for weight loss, maintenance, or muscle gain.

Health & Fitness

Rent vs Buy Calculator

Compare the financial impact of renting vs buying a home. See the break-even point and total costs over time to make an informed housing decision.

Home & DIY

Square Footage Calculator

Calculate square footage for rooms, flooring, painting, and landscaping. Enter length and width to find total area in square feet or square meters.

Home & DIY

Sales Tax Calculator

Calculate sales tax for any purchase. Enter the price and tax rate to find the total cost including tax, or work backwards from the total to find the pre-tax price.

Math

MPG Calculator

Calculate your vehicle's fuel efficiency in miles per gallon. Track your gas mileage, compare fill-ups, and monitor your car's fuel economy over time.

Auto

Sleep Calculator

Calculate the best time to sleep or wake up based on sleep cycles. Wake up feeling refreshed by timing your sleep to complete full 90-minute cycles.

Health & Fitness

Paint Calculator

Calculate how much paint you need for your room or project. Enter room dimensions and get accurate estimates for gallons needed, including doors and windows.

Home & DIY

Pace Calculator

Calculate running pace, finish time, or distance. Perfect for runners and joggers training for races. Find your pace per mile or per kilometer.

Health & Fitness

Profit Margin Calculator

Calculate profit margin, markup, and gross profit for your business. Enter cost and selling price to find margin percentage and optimize your pricing strategy.

Business

Recipe Scaler Calculator

Scale any recipe to serve more or fewer people. Enter the original serving size and ingredient amounts, then adjust to your desired number of servings.

Cooking

Grade Calculator

Calculate your current grade and what you need on the final exam. Enter assignment scores and weights to find your overall grade in any class.

Math

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