Everyday calculators
Small calculations that come up in the middle of something else — a date, a split bill, a unit price, a grade you still need. They are meant to take a few seconds and give you an answer you can act on straight away.
What is today?The date, public holidays, international days, what happened on this day, famous birthdays, sunrise, sunset and the moon.See today →Add business days calculatorFind the date a number of working days after a start date (weekends skipped).Add or subtract days from a dateFind the date a number of days before or after a starting date.Age calculatorWork out your exact age in years, months and days from your birth date.Age in days calculatorConvert your age into total days, weeks and approximate years.Anniversary CalculatorHow long has it been, exactly? Years, months and days elapsed since a wedding, a first date, a friendship or a first day at work, the total in days, weeks and hours, the countdown to the next anniversary, the milestones coming up (10 000 days, silver, gold) and — for weddings — the traditional and modern gift for that year, in both the British and the American lists.Autumnal Equinox CalculatorGet the exact instant of the autumnal equinox and of all four seasonal markers for any year, in UTC and in your own offset, with northern and southern naming and the length of each astronomical season.
Coffee habit cost calculatorSee how much your daily coffee habit costs per month and per year.Cost per use calculatorWork out the real cost per use of a purchase to judge if it's worth it.Discount calculatorFind the sale price and how much you save from an original price and a discount.Discount percentage finderFind the discount percentage from an original price and a sale price.Electricity bill calculatorEstimate an electricity bill from kWh used and the price.Gift Card Tip CalculatorBill + tip minus a gift-card balance = the cash you still owe, split between people if needed.
AP Score CalculatorPredict your 1–5 AP exam score from multiple-choice and free-response performance, by subject curve.Attendance Percentage CalculatorWork out your attendance percentage and how many classes you can miss — or must attend — to hit a target.Cornell notes generatorBuild a clean Cornell-method note sheet as you type. Enter your topic, cues or questions, main notes and a summary, and it lays them out in the classic three-zone Cornell format — narrow cue column, wide notes column and a summary bar — with a live preview you can download as a printable HTML page.Easy Grader (EZ Grader)Turn a number of questions and wrong answers into a percentage and letter grade, or the whole grading chart.Final grade calculatorFind the score you need on your final exam to reach a target overall grade.Flashcard spaced repetition scheduler (SM-2)The next review date for a flashcard using the SM-2 algorithm that powers Anki and SuperMemo. Grade how well you recalled the card (0–5) and give its current state — repetitions, ease factor and last interval — and it computes the new interval, the updated ease factor and when to see the card next.
Unit converterConvert length, mass, temperature, volume, area, speed, time and data — m, km, mi, ft, in, kg, lb, oz, °C, °F, K, L, gal, ha, acre, km/h, mph, knots, MB, GiB and more.Angle converterConvert between deg, rad, gon and more. Free angle converter, instant and accurate.Area converterConvert between cm², m², ha, acre, km² and more. Free area converter, instant and accurate.Bandwidth converterConvert between kbps, Mbps, Gbps and more. Free bandwidth converter, instant and accurate.Cooking converterConvert between tsp, tbsp, cup, mL and more. Free cooking converter, instant and accurate.Data storage converterConvert between B, KB, MB, GB, TB and more. Free data storage converter, instant and accurate.
Carbon Footprint CalculatorEstimate your yearly CO2 footprint from transport, home energy, diet and shopping.Electricity consumption calculatorWork out an appliance's energy use in kWh.Flight carbon footprint calculatorEstimate the CO₂ emissions of a flight from its distance.Heat index calculatorFind the 'feels-like' temperature in hot, humid weather.Water Usage CalculatorEstimate your household's daily, monthly and yearly water use from showers, toilets, laundry, dishwasher and more.Wind chill calculatorFind the 'feels-like' temperature in cold, windy weather.
Closet capsule outfit calculatorA small mix-and-match wardrobe makes a surprising number of outfits. Tops × bottoms, plus each dress, multiplied by your layering options and — if you count them — your shoes: the combinations add up fast.Clothing size converterTops, bottoms and shirt collars converted separately between FR, IT, DE, UK and US — each with the body measurement EN 13402 makes its primary dimension.Commute Life Wasted CalculatorSee how many hours, full days and years of your life your commute adds up to — and what you could have done instead.Dew Point CalculatorDew point from air temperature and relative humidity (Magnus formula), with a comfort band.Diaper Size CalculatorThe right nappy size for your baby's weight, how many you'll use, and when to size up.Dishwasher Load OptimizerEnter what needs washing to see how many cycles you need and whether the next load is full enough to run.