🔢 Calculators
Health, date, and everyday calculators
- Age CalculatorEnter your date of birth and a reference date to get your exact age in years, months and days, plus the number of days until your next birthday.
- BMI Calculator (WHO)Work out your BMI from height (cm) and weight (kg) with the WHO and US CDC adult categories, and see the weights where the category changes at your height.
- Date CalculatorCount the days, months and years between two dates, or find the date a number of days or months before or after. Useful for work tenure or contract end dates.
- Days Until Calculator (D-day)See how many days are left until an exam, trip or deadline in D-day format. Past dates show the D+ day count.
- Japanese BMI Calculator (JASSO)Get your BMI from height (cm) and weight (kg) under Japan's JASSO standard and see your obesity grade (1–4) and the weights where it changes at your height.
- Korean BMI Calculator (KSSO)Work out your BMI from height (cm) and weight (kg) under Korea's KSSO 2024 guideline and see your obesity class and the weights where it changes at your height.
- Percentage CalculatorCalculate percentages, percentage change and discounts, or recover the original price from a sale price and discount. Six calculations on one screen.
- Aspect Ratio CalculatorGet the simplified aspect ratio (like 16:9) from a width and height, or the missing side from a ratio. With common resolutions and a CSS aspect-ratio value.
- Baby Age in Months CalculatorEnter your baby's date of birth to see how many months and days old they are and the date they reach the next month. Corrected age for preemies is optional.
- Compound Interest CalculatorFinal balance, total interest and effective annual rate from a principal, rate, term and yearly-to-daily compounding. Regular contributions are optional.
- Due Date Calculator (Weeks Pregnant)Estimate a due date from your last period, conception, embryo transfer or ultrasound. See gestational age on a reference date, days left and key milestones.
- EU Protein Intake Calculator (EFSA)Calculate EFSA’s protein PRI in grams per day using your weight, or the reference weight if left blank. Pregnancy and breastfeeding additions are included.
- German Protein Intake Calculator (DGE)DGE daily protein (g), based on your weight or the reference weight if blank. Includes age-65+ estimates and pregnancy and breastfeeding additions.
- Germany VAT (MwSt) CalculatorCalculate Germany's VAT (MwSt) at 19% and 7%: get gross from net, or net and tax from gross. Includes cent rounding and the restaurant 7% food rule.
- Japan Consumption Tax CalculatorCalculate Japan's 10% consumption tax (8% reduced rate) from a pre-tax price, or reverse it from a tax-included price. Choose round down, half-up, or up.
- Japanese Protein Intake Calculator (DRIs 2025)Daily protein by sex and age in Japan's 2025 DRIs: recommended intake, average requirement, pregnancy and breastfeeding additions and a figure for your weight.
- Korea VAT CalculatorAdd 10% VAT to a supply value, or split a VAT-included total into supply value and tax. Tax is rounded down to the nearest won, with the formula shown.
- Korean Age CalculatorEnter your date of birth to get Korea's three ages at once: international age, year age and counting age, plus which one is used when since the 2023 age law.
- Korean Anniversary Calculator (100 Days)Enter the day you started dating or a baby's birthday to see today's day count, plus dates for the 100th, 200th, 1000th days and 1st-3rd anniversaries.
- Korean Lunar Calendar ConverterConvert between solar and Korean lunar dates by KASI's calendar: Seollal and Chuseok, leap months, zodiac year, a month view and 10 years of lunar birthdays.
- Korean Military Discharge Date Calculator & Card MakerEnter an enlistment date and branch to estimate a South Korean soldier's discharge date, D-day countdown, service progress, then save a shareable card.
- Korean New Year Money (Sebaetdon) CalculatorPick a relationship and school level for a recommended amount, reasons and a survey reference amount. A total budget lowers it, never below the range minimum.
- Korean Protein Intake Calculator (2025 KDRIs)Daily protein by sex and age in the 2025 KDRIs: recommended intake, average requirement, pregnancy and breastfeeding additions and a figure for your weight.
- Korean Pyeong to Square Meter ConverterConvert Korean pyeong and square meters using 1 pyeong = 400/121 m². Convert apartment exclusive and supply areas to pyeong separately.
- Korean Son Eomneun Nal Calendar (Lucky Moving Days)Find Korea's son-free days (son eomneun nal), lunar days ending in 9 or 0, on a calendar or in a list for the next 3, 6 or 12 months, with a weekend filter.
- Korean Wedding Gift Money CalculatorEnter your relationship, closeness, attendance, meal cost, travel and what they gave you to see a survey reference amount and a rule-based one, with reasons.
- Loan CalculatorEnter a loan amount, rate and term to compare equal payment, equal principal and interest-only: monthly payment, total interest, yearly and monthly schedules.
- Ovulation Calculator (Fertile Window)Estimate your ovulation date, fertile window and next period from your last period and cycle length, shown on a calendar. Not a form of birth control.
- Running Pace CalculatorFind your pace per km or mile and your speed from distance and time, or a finish time or distance from a target pace. Includes splits and Riegel predictions.
- Sleep Calculator (Bedtime & Wake-Up Time)Enter a wake-up time or bedtime to get times by number of sleep cycles (90 min by default) with total sleep, checked against the 7-hour adult guideline.
- South Korea Minimum Wage Calculator 2026Work out weekly, monthly (209 hours) and annual pay plus weekly holiday pay at Korea's 2026 minimum wage of KRW 10,320 an hour, and check your salary.
- South Korea Minimum Wage Calculator 2027Work out weekly, monthly (209 hours) and annual pay plus weekly holiday pay at Korea's 2027 minimum wage of KRW 10,700 an hour, and check your salary.
- South Korea Weekly Holiday Pay Calculator 2026Calculate Korea's 2026 weekly holiday pay (juhyu sudang) from your hourly wage and contracted hours, with the 15-hour rule, attendance and a monthly average.
- South Korea Weekly Holiday Pay Calculator 2027Calculate Korea's 2027 weekly holiday pay (juhyu sudang) from your hourly wage and contracted hours, with the 15-hour rule, attendance and a monthly average.
- Spain IVA (VAT) CalculatorCalculate Spain's IVA at 21%, 10%, or 4% — get the total from the taxable base, or split a total into base and tax. Includes recargo de equivalencia.
- Time CalculatorAdd or subtract multiple durations in hours:minutes, hours:minutes:seconds or minutes:seconds. See the total in time, minutes and seconds.
- UK VAT CalculatorAdd UK VAT (20%, 5%, 0%) to a net amount or remove it from a gross amount. Reverse VAT uses the VAT fraction (1/6, 1/21) and rounds to the nearest penny.
- US Protein Intake Calculator (DRI/RDA)Calculate protein RDA in grams per day under US–Canadian DRI using your weight, or the reference weight if blank. Includes late pregnancy and breastfeeding.
What you can do with the Calculators
There are calculators for ages and dates, finance calculators such as percentage, compound interest and loan repayment, and health calculators such as BMI and protein intake. Enter your values and the result appears right away. At the bottom of the page you can check how it’s calculated and what sources it’s based on.
Things to know
Where the standard differs from country to country, the calculator has a separate page for each country (or for the international standard), and the title says which standard it uses. Choose the page for the standard that applies to you. Calculators that use figures set by law show the “Effective from” date and the “Last verified” date. Results related to health, finance and law are for reference only and don’t replace professional advice.