Free Calculators
These calculators answer everyday questions with exact numbers: how old you are to the day, your BMI and healthy weight range, how much interest an extra mortgage payment saves, how many cubic yards of gravel or soil a project needs, and when to go to bed to wake up between sleep cycles. Each one shows its formula so you can check the math.
16 tools · Updated
All Calculators
Age Calculator — How Old Am I?
Free age calculator online. Calculate your exact age in years, months, days, hours, and minutes from your date of birth. How old am I today?
Age Difference Calculator — Age Gap Calculator
Free age difference calculator. Calculate the exact age gap between two people in years, months, and days. Sibling and dating age gap calculator.
BMI Calculator — Check Body Mass Index Online
Free BMI calculator. Check your Body Mass Index online and find out if you are underweight, normal, overweight, or obese. Instant results.
Mortgage Payoff Calculator — Extra Payment Calculator
Free mortgage payoff calculator. See how fast you can pay off your mortgage with extra payments and calculate total interest saved over the loan term.
HELOC Calculator — Home Equity Line of Credit
Free HELOC calculator. Calculate your home equity line of credit payments, interest costs, and borrowing power. Home equity loan calculator with amortization.
Snow Day Calculator — Snow Day Predictor
Free snow day calculator with real weather data. Enter your ZIP code to predict the chance of school closing. 3-day forecast with probability percentage.
Cubic Yard Calculator — Dirt, Gravel, Mulch, Stone
Free cubic yard calculator for dirt, gravel, mulch, stone, and concrete. Calculate how many yards of material you need for your landscaping project.
Stair Calculator — Stair Stringer Calculator & Rise and Run
Free stair stringer calculator. Calculate stair rise and run, number of steps, stringer length, and tread depth. Deck stair calculator with diagram.
Sleep Calculator — Bedtime & Wake Up Time
Free sleep calculator. Find the best time to sleep and wake up based on 90-minute sleep cycles. Sleep planner for optimal rest and energy levels.
Percentage Calculator — Find Percentage Online
Free percentage calculator. Find percentage of a number, calculate percentage increase, decrease, and difference between two values instantly.
Aspect Ratio Calculator — Resize & Scale
Free aspect ratio calculator. Calculate, convert, and scale aspect ratios for video, images, and screens. Find width or height from any ratio like 16:9, 4:3, 21:9.
Days Between Dates Calculator
Free days between dates calculator. Calculate the exact number of days, weeks, and months between two dates. Date difference calculator online.
Garden Calculator — Soil, Mulch & Plant Spacing
Free garden calculator. Calculate how much soil, mulch, compost, and seeds you need for your garden beds. Plant spacing calculator for landscaping projects.
Terminus Calculator — Deadline & Date Planner
Free terminus calculator. Calculate terminus dates and deadlines for legal, academic, and business purposes. Add or subtract days from any date easily.
Rock Calculator — Landscaping Rock & Gravel
Free landscaping rock calculator. Calculate how much rock, gravel, or decorative stone you need in tons and cubic yards for your landscape project.
Starbucks Calorie Calculator — Drink Nutrition
Free Starbucks calorie calculator. Calculate calories, sugar, fat, and nutrition for any Starbucks drink with custom size, milk, and syrup options.