200+ free online calculators — fast, accurate, no sign-up
Free mortgage calculator: estimate monthly payments, total interest, and full amortization schedule. Compare 15-year vs 30-year loans, see PMI and tax impact. Make informed home buying decisions.
Free home affordability calculator: find out how much house you can afford based on income, debts, down payment, and interest rate. Uses the 28/36 DTI rule. Estimate your buying power today.
Calculate your monthly car loan payments, total interest, and see the full amortization schedule
Free loan calculator: calculate monthly payments, total interest, and total cost for personal loans, auto loans, and more. Compare bi-weekly vs monthly payments. No sign-up required.
Free payment calculator: find the optimal loan term or monthly payment for your budget. Calculate how much you need to pay each month to meet your financial goals.
Free compound interest calculator: see how your investments grow over time with daily, monthly, or yearly compounding. Calculate future value, total interest, and plan your retirement savings.
Free tip calculator: calculate the perfect tip amount for any bill percentage. Split the bill among any number of people. Ideal for restaurants, bars, and group dining.
Free SIP calculator: see how monthly mutual fund investments grow with compounding, compare systematic investing vs lump sum, and estimate returns and maturity value.
Free FIRE calculator: find your financial independence number with the 4% rule, see years to retirement, projected FIRE age, and safe withdrawal rate.
Free savings goal calculator: find out how long it takes to reach any target or how much to save each month. Plan for emergencies, down payments, and big purchases.
Free mortgage break-even calculator estimates how many months refinance payment savings need to recover your upfront closing costs.
Free debt payoff calculator with extra payments compares payoff time, total interest, and savings for one fixed-rate balance.
Free profit margin calculator for gross margin, profit percentage, and profit left after costs.
Free hourly to salary calculator: convert an hourly wage into annual, monthly and weekly pay, or turn any annual salary back into an hourly rate.
Free VAT calculator to add or remove VAT in one step: get the net amount, the VAT charged, the gross price and the effective rate for any rate you enter.
Free health and fitness calculator hub: BMI, BMR, TDEE, body fat, ideal weight, lean body mass and daily water in one place, plus links to every health tool.
Free BMI calculator for men and women: get your Body Mass Index, WHO health category and healthy weight range instantly in metric or imperial units.
Free body fat calculator using the US Navy method: estimate your body fat percentage for men and women from simple circumference measurements.
Free ideal weight calculator: find your healthy body weight range from height and gender with the Devine, Robinson and Miller formulas.
Free lean body mass calculator estimates lean mass and body fat percentage from height and weight using the Boer and James formulas for men and women.
Free body shape calculator: find your body type (hourglass, pear, apple, rectangle or inverted triangle) from bust, waist and hip measurements.
Free BMR calculator using the Mifflin-St Jeor equation: get your basal metabolic rate and daily calorie needs from weight, height and age.
Free TDEE calculator: estimate your total daily energy expenditure and maintenance calories from BMR and activity level for weight goals.
Free calorie deficit calculator shows how many calories to eat each day to lose weight at your chosen pace, based on your TDEE and a safe weekly deficit.
Free calories burned calculator: estimate how many calories you burn walking, running, cycling, swimming and 15+ activities. Uses 2024 Compendium MET values.
Free macro calculator: daily calories plus protein, carb and fat grams for weight loss, muscle gain or maintenance. Enter your age, sex, height and weight.
Free protein calculator: daily protein needs in grams from body weight and activity, from the 0.8 g/kg RDA to 2.0 g/kg for athletes and muscle gain.
Free keto calculator: enter your body stats, activity level and goal to get a calorie target plus daily net-carb, protein and fat grams for standard keto.
Free water intake calculator tells you how much water to drink per day based on body weight and exercise, following the 30-35 ml per kg guideline.
Free VO2 max calculator estimates cardiorespiratory fitness from a 12-minute run or resting heart rate, with age- and sex-based fitness categories.
Free running pace calculator converts time and distance into pace per kilometer or mile, speed, and predicted 5K, 10K, half and full marathon times.
Free heart rate zone calculator finds your five training zones from age and resting heart rate using the Karvonen formula for fat burn and cardio.
Free VO2 max estimate from running pace.
Free cycling VO2 max calculator that estimates aerobic capacity in mL/kg/min from your best five-minute power and body weight using the ACSM cycling equation.
Free sleep calculator: get bedtimes from your wake-up time or wake-up times from your bedtime, using 90-minute sleep cycles and 7-9 hour age recommendations.
Free due date calculator using Naegele's Rule: estimate your baby's arrival date from your last period or conception date, week by week.
Free blood type calculator: predict your baby's blood type from the parents' ABO types with probability percentages and Rh risk.
Free blood compatibility checker: see who you can donate to and receive from by ABO and Rh type, with universal donor status.
Free dog age calculator converts dog years to human years using the DNA methylation formula and size-based AVMA estimates, with puppy-to-senior life stages.
Free cat age calculator converts cat years into human years and identifies your cat life stage from kitten to senior using veterinary guidelines.
Free kids BMI calculator: get your child's Body Mass Index and CDC age-and-sex percentile with healthy weight range
Free time unit converter: convert between milliseconds, seconds, minutes, hours, days, weeks, months, years, decades, and centuries. Fast and accurate time conversion.
Free shoe size converter: convert between US, UK, EU, JP shoe sizes and foot length in centimeters and inches. Perfect for international online shoe shopping.
Free online unit converter: convert between units of length, weight, temperature, area, and volume. Fast and accurate conversions for everyday use, cooking, travel, and work.
Free length converter: convert between meters, feet, inches, centimeters, miles, kilometers, and more. Height converter, distance converter, and metric-imperial conversion.
Free weight converter: convert between kilograms, pounds, ounces, grams, and more. Perfect for cooking, fitness, shipping, and everyday weight conversions.
Free temperature converter: convert between Celsius, Fahrenheit, Kelvin, and more. Oven temperature converter, weather conversion, and scientific temperature conversion.
Free area converter: convert between square meters, acres, hectares, square feet, square miles, and more. Perfect for real estate, land measurement, and construction.
Free volume converter: convert between liters, gallons, cups, milliliters, pints, quarts, and more. Cooking converter, liquid volume conversion, and baking measurements.
Free speed converter: convert between km/h, mph, knots, m/s, and more. Perfect for travel planning, running pace conversion, and wind speed comparison.
Free data storage converter: convert between bytes, KB, MB, GB, TB, PB, and more. Perfect for file size conversion, storage planning, and tech specifications.
Free pressure converter: convert between Pa, kPa, Bar, PSI, atmospheres, and more. Tire pressure converter for automotive and industrial use.
Free age calculator: find out your exact age in years, months, and days. Calculate how many total days, hours, and minutes you have been alive. Also find days until your next birthday.
Free time calculator: add, subtract, and calculate time durations in hours, minutes, and seconds. Perfect for tracking work hours, cooking times, or any time-based calculations.
Free date calculator: add or subtract days, weeks, or months from any date. Calculate the exact difference between two dates including business days. Perfect for project planning.
Free business days calculator: calculate working days between two dates or add business days to any date. Excludes weekends and holidays. Essential for project planning and contracts.
Free home renovation material calculators: estimate paint, wall and floor tiles, wallpaper, flooring, concrete, bricks, grout, curtains, drywall, stairs, gravel, roofing, fencing, decking, carpet, siding, mulch, insulation and pavers. Plan your DIY or contractor project accurately.
Free paint calculator: estimate how many liters or gallons of paint you need for any room. Input wall area, number of coats, and paint coverage. Prevent overbuying or running short.
Free wall tile calculator: calculate how many tiles and boxes you need. Input wall area, tile size, and waste percentage. Perfect for bathroom, kitchen, and backsplash tiling projects.
Free floor tile calculator: how many floor tiles and boxes you need. Enter floor area, tile size and waste percentage for living rooms, kitchens and bathrooms.
Free wallpaper calculator: find out how many rolls of wallpaper you need. Enter wall area, roll dimensions, and pattern repeat. Avoid buying too many or too few rolls.
Free flooring calculator: calculate how many boxes of laminate, hardwood, or vinyl flooring you need. Enter room area, plank size, and boxes per pack. Includes waste factor for cuts.
Free concrete calculator: estimate concrete volume and material quantities for slabs and footings. Input length, width, depth, and mix ratio. Get cement bags, sand, and gravel estimates.
Free brick calculator: calculate how many bricks and how much mortar you need for a wall. Enter wall area, brick dimensions, and waste percentage. Essential for masonry projects.
Free grout calculator: estimate how much tile grout you need by weight and volume. Input tile size, joint width, and density. Avoid buying too much or running out mid-project.
Free curtain fabric calculator: calculate how many meters of fabric you need. Enter window dimensions, fullness ratio, and fabric width. Perfect for custom curtains and drapes.
Free drywall calculator: estimate how many plasterboard sheets, joint compound, screws, and tape you need. Enter wall area and sheet size. Ideal for partition walls and renovations.
Free stair calculator computes steps, riser height, tread depth, stringer length and stair angle from your rise and target riser, using code-friendly design rules.
Free gravel calculator estimates gravel volume in cubic meters and weight in tonnes for driveways, paths and gardens. Enter area, depth and material type.
Free shingle calculator estimates shingle bundles, underlayment rolls and nails from roof footprint and pitch, with squares and project cost.
Free fence calculator plans wood or chain link fences: posts, rails, panels and total cost from your property line dimensions.
Free deck calculator estimates decking boards, joists, fasteners and material cost from your deck area and board dimensions.
Free carpet calculator estimates carpet area, roll length and total cost for any room, with waste allowance for cuts and joins.
Free siding calculator estimates vinyl siding area, boxes and project cost. Enter wall dimensions and waste allowance for accurate material needs.
Free mulch calculator estimates garden bed mulch volume, bags and cost, and compares bagged vs bulk prices. Enter bed size and depth for bark or wood chips.
Free insulation calculator estimates rolls, batts or blown-in bags for attics, walls and floors based on your target R-value, with coverage and cost.
Free paver calculator counts patio or driveway pavers, sand base and joint sand, with cost estimates for any paver size.
Free stair carpet calculator to estimate the carpet area needed for treads and risers, including a practical waste allowance.
Free grade calculator: calculate your weighted grade average and track your academic performance. Add multiple assignments with different weights to find your overall course grade.
Free GPA calculator: calculate your Grade Point Average on a 4.0 or 5.0 scale. Track semester and cumulative GPA for high school or college. Supports letter grades and percentages.
Free final exam calculator: calculate what grade you need on your final exam to achieve your target course grade. Works with weighted grading systems. Plan your study strategy.
Free percentage calculator: calculate what percent one number is of another, find percentage increases and decreases, and solve percent problems. Fast and accurate.
Free basic online calculator for everyday arithmetic: addition, subtraction, multiplication, and division. Simple, clean interface for quick calculations.
Free online scientific calculator with trigonometric, logarithmic, exponential, and statistical functions. Perfect for students, engineers, and professionals.
Free Roman numeral converter for numbers 1-3999: instantly converts any number to standard Roman numerals with a numeral chart and date examples like MMXXIV.
Free z-score calculator: enter a value, mean and standard deviation to get the z-score and percentile rank for test scores and growth charts.
Free fraction calculator: add, subtract, multiply or divide two fractions and get the simplified result, mixed number, decimal and percentage in seconds.
Free probability calculator: instantly find P(A and B), P(A or B) and conditional probabilities for independent or dependent events with clear results.
Free triangle calculator: enter three sides to instantly find the area, perimeter and all angles, and classify right, isosceles or equilateral shapes.
Free standard deviation calculator: enter numbers to get standard deviation, variance, mean and sum for a population or sample, with the exact formula.
Free confidence interval calculator: enter the sample mean, standard deviation and size to get the margin of error and 90%, 95% or 99% interval instantly.
Free volume calculator for cubes, boxes, cylinders, spheres and cones. Get instant results in cm³, liters, gallons, cubic feet and cubic inches. Select a shape.
Free password generator: create strong, secure, random passwords with customizable length, uppercase, lowercase, numbers, and symbols. Generate uncrackable passwords instantly.
Free random number generator: generate random numbers within any range. Perfect for lotteries, giveaways, games, statistical sampling, and decision making.
Free discount calculator: calculate savings and final price after any percentage discount. Add sales tax for the final out-the-door price. Perfect for shopping and sales.
Free fuel cost calculator: estimate trip fuel costs based on distance, fuel consumption rate, and current fuel prices. Plan your road trip budget and compare vehicle efficiency.
Free electricity cost calculator for estimating daily, monthly, and annual energy charges from kWh usage and your tariff.
Free wire size calculator for estimating copper conductor area from voltage, current, cable length, and permitted voltage drop.
Free pool heater BTU calculator for estimating the heater output needed to raise pool water to a target temperature in a chosen time.
Free battery life calculator: convert mAh and volts into watt-hours, then divide by your device's wattage to see how many hours one charge will last.