Everyday calculator
Age, percentages, dates, BMI and loan interest in one placeEnter a date of birth to see the age.
Age
- Next birthday in
- Days lived
- Korean year age
- Traditional Korean age
Since June 2023, Korean law, contracts and official documents use international age. Year age is only used where a law says so, such as military service and youth protection.
People born on February 29 are counted one year older on March 1 in non-leap years.
What is Y% of X?
Answer
X is what percent of Y?
Answer
Percent change from X to Y?
Answer
X increased or decreased by Y%?
Answer
Korean VAT (10%)
VAT is 10% of the supply value. Working back from a total, VAT is total × 10/110.
- Supply value
- —
- VAT
- —
- Total
- —
Computing the tax per item and rounding each before adding can differ slightly from the tax computed once on the total.
Days between two dates
- In weeks
- In months
Pick two dates to see how many days apart they are.
Add or subtract days (D-day)
Enter height and weight to see your BMI.
- Total interest
- Total paid
| No. | Payment | Principal | Interest | Balance |
|---|
About this tool
Work out an exact age, percentages, the days between two dates or a date N days away, BMI and loan interest on one page. For loans you get the monthly payment, total interest and a full schedule for equal-payment, equal-principal and interest-only repayment.
How to use it
- 1 Pick Age, Percent, Dates, BMI or Loan from the tabs.
- 2 Type dates or numbers — the answer updates as you type. There is no button to press.
- 3 On the Loan tab, open the schedule to see principal, interest and balance for every payment.
Good to know
- Loan interest uses the annual rate divided by 12. Lenders that charge daily interest can differ by a few cents per payment
- Prepayment fees, grace periods and variable rates are not supported
- BMI is not a reliable measure for children and teens, during pregnancy, or for very muscular people
Frequently asked questions
How is age calculated?
It is the number of birthdays you have had: this year minus your birth year, minus one more if your birthday has not come yet this year. If you were born on February 29, you turn a year older on March 1 in non-leap years.
Does the D-day count include the first day?
By default the day after the start date is day 1. For anniversaries where the first day counts as day 1, such as 100 days together, turn on the anniversary option and the date moves one day earlier.
What is the difference between equal payments and equal principal?
With equal payments you pay the same amount every month. With equal principal you pay more at first and less over time, and the total interest is lower. Interest-only loans repay the principal at the end, so they cost the most interest.
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