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Fast, accurate answers for money, health, math and dates, with every formula explained and worked examples you can check.
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- Formulas explained
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Every tool shows how the result is calculated.
Finance
View allLoan Calculator
Monthly payment, total interest and amortization schedule.
Mortgage Calculator
Full monthly housing payment with taxes, insurance and PMI.
Compound Interest Calculator
Growth of savings with compounding and contributions.
Retirement Calculator
Project your nest egg and retirement income.
Auto Loan Calculator
Car payment with trade-in, tax and fees.
Savings Goal Calculator
Monthly saving needed to reach a goal.
Credit Card Payoff Calculator
Months to debt-free and total interest.
Debt-to-Income Ratio Calculator
Front-end and back-end DTI for lenders.
Inflation Calculator
Future cost and lost purchasing power.
ROI Calculator
Total and annualized return on investment.
Simple Interest Calculator
Interest on principal without compounding.
Salary to Hourly Calculator
Annual salary ↔ hourly, weekly and monthly pay.
House Affordability Calculator
Maximum home price by income and debts.
CAGR Calculator
Compound annual growth rate between two values.
Coast FIRE Calculator
How much you need invested today to stop saving.
FIRE Number Calculator
Your early-retirement target and years to reach it.
Mortgage Points Calculator
Break-even time for buying discount points.
Prorated Rent Calculator
Rent for a partial move-in or move-out month.
Cap Rate Calculator
Net operating income ÷ property value.
Cash-on-Cash Return Calculator
Annual cash flow ÷ cash you invested.
Rule of 72 Calculator
Years to double money at a given rate.
APY Calculator
APR ↔ APY for any compounding frequency.
Stock Average Calculator
Average cost per share and shares to average down.
Raise Calculator
New pay after a raise, per year, month and hour.
Overtime Calculator
Time-and-a-half and double-time pay.
Freelance Rate Calculator
The hourly rate that replaces a salary.
Emergency Fund Calculator
Your emergency fund target and time to reach it.
Sinking Fund Calculator
Monthly savings to pay for a planned expense.
Business
View allMarkup Calculator
Price from cost plus markup, and markup vs margin.
Break-Even Calculator
Units and revenue needed to cover fixed costs.
CPM Calculator
Cost per 1,000 ad impressions.
ROAS Calculator
Revenue per dollar of ad spend.
Churn Rate Calculator
Customers lost as a share of customers at the start.
Customer Lifetime Value Calculator
Gross profit a customer brings over time.
Employee Cost Calculator
Salary plus payroll taxes and benefits.
Commission Calculator
Commission on sales, flat or tiered.
Home & Garden
View allMulch Calculator
Cubic yards and bags for a garden bed.
Gravel Calculator
Cubic yards and tons of gravel or stone.
Fence Post Concrete Calculator
Bags of concrete to set fence posts.
Paver Base Calculator
Gravel base, sand and pavers for a patio.
Drywall Calculator
Sheets of drywall for walls and ceiling.
Wallpaper Calculator
Rolls of wallpaper by the strip method.
Tile Calculator
Tiles and boxes for a floor or wall.
Pool Volume Calculator
Gallons in a rectangular, round or oval pool.
Grass Seed Calculator
Pounds of seed for a new lawn or overseeding.
Space Heater Cost Calculator
Electricity cost of a space heater.
EV Charging Cost Calculator
Cost per charge and per mile for an EV.
BTU Calculator
AC size in BTU for a room.
Health & Fitness
View allBMI Calculator
Body mass index with healthy weight range.
Calorie Calculator
Daily calories to maintain, lose or gain weight.
BMR Calculator
Calories burned at complete rest.
Body Fat Calculator
Body fat % from tape measurements.
Ideal Weight Calculator
Ideal body weight by four clinical formulas.
Macro Calculator
Daily protein, carbs and fat in grams.
Due Date Calculator
Estimated due date and current week of pregnancy.
Caffeine Calculator
Caffeine left in your body at bedtime.
Waist-to-Height Ratio Calculator
Waist ÷ height and health risk.
Steps to Miles Calculator
Steps to miles and km by stride length.
Pace Calculator
Running pace, finish time or distance.
Pets
View allDog Age Calculator
Dog years to human years by breed size.
Cat Age Calculator
Cat years to human years and life stage.
Dog Chocolate Toxicity Calculator
Theobromine dose and risk after eating chocolate.
Puppy Weight Calculator
Estimated adult weight of a puppy.
Dog Pregnancy Calculator
Whelping due date and pregnancy timeline.
Dog Food Calculator
Daily calories and cups of dog food.
Math
View allPercentage Calculator
Three percentage problems, solved with steps.
Percentage Change Calculator
Percent increase, decrease and difference.
Fraction Calculator
Fraction arithmetic with simplified results.
Standard Deviation Calculator
Standard deviation, variance, mean and median.
Quadratic Equation Calculator
Roots, discriminant and vertex with steps.
GPA Calculator
Semester and cumulative GPA on a 4.0 scale.
Final Grade Calculator
Score needed on the final exam.
Ratio Calculator
Simplify ratios and solve proportions.
Conversions
View allCups to Grams Converter
Baking conversions by ingredient.
Roman Numeral Converter
Numbers ↔ Roman numerals with breakdown.
Number Base Converter
Binary, octal, decimal and hex conversion.
Oven Temperature Converter
°C, °F, fan oven and gas mark.
Baker’s Percentage Calculator
Dough ingredients from baker’s percentages.
Pizza Dough Calculator
Dough recipe for any number of pizzas.
Yeast Converter
Fresh ↔ active dry ↔ instant yeast.
Turkey Cooking Time Calculator
Roasting and thawing times for a turkey.
Coffee Ratio Calculator
Grams of coffee for any brew method.
Date & Time
View allAge Calculator
Exact age and days to next birthday.
Days Between Dates Calculator
Days, weeks and months between two dates.
Date Calculator
Add or subtract time from a date.
Time Duration Calculator
Hours and minutes between two times.
Hours Worked Calculator
Weekly timesheet with breaks and pay.
Chronological Age Calculator
Exact age on a test date (years;months.days).
Military Time Converter
AM/PM ↔ 24-hour military time.
Business Days Calculator
Working days between dates, excluding holidays.
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Tested for accuracy
Every calculator is checked against known values and published formulas before it goes live.
Formulas explained
See exactly how each result is calculated, with worked examples you can follow step by step.
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Calculations run in your browser. What you type is never sent to our servers.
Instant on any device
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