Days Calculator

Calculate what the date is when adding or subtracting days from a base date. For example, calculate 30 days from today, or 90 days from an event date. Calculate by calendar days, or business days.

Add or Subtract Number of Days

How many days to add or subtract to date

No: Calendar days Sun-Sat. Yes: Business days Mon-Fri

Entry Fields

Use the From Date field to specify the base date to which to apply the number of days you want to add or subtract. The base date can be today's date, or a past or future date. The from date defaults to today's date.

In Date Operation, select either Add or Subtract. For example, to find out what the date will be 180 days from the current date, use Add; Or, to see what date is was 60 days ago, enter subtract.

Number of Days is used to calculate the date that occurs that many days after (for add operation) or before (for subtract operation) the From Date you've specified.

Set Business Days Only? to No, the default, to base the calculator on calendar days, which means that the number of days includes all days of the week: Sunday through Saturday. For example, if the current date is the first Friday in June, and you want to calculate 37 days from now, the count starts by including the next day, Saturday, then advancing by 1 day to Sunday, then Monday, etc.

Set Business Days Only? to Yes to include only business days in the count of days. The calculator considers business days to be Monday through Friday. If you want to determine the date which occurs 30 business days from today, and today is the first Friday in June, the first day considered is the following Monday; Any Saturday or Sunday that occur within the number of days you want to add or subtract are always excluded.

Days Chart

If you opt to calculate with business days, a days chart showing each date and its corresponding day number is displayed if you are adding or subtracting 366 days or less.

If you are subtracting days from a date, each day number is shown as a negative. For example, the first day prior to your base date is -1 day.

About Calendar and Business Days Calculator

This calculator determines what the date is after a fixed number of days are either added or subtracted from a base date.

If you add days to today's date (or a date in the future), the new date will be in the future; Similarly, if you subtract days from the current date (or a date in the past), the resulting date will be in the past. However, this date calculator is extremely flexible, enabling you to add or subtract days from past/future dates. For example, if it is currently May 2023, and you provide a base date of January 1, 2023 and opt to add 60 calendar or business days to it, the result will also be in the past.

By default, when you add or subtract days to a date, the calculation is done using calendar days. This means that all days of the week are counted, Monday through Sunday. Calculating dates with calendar days occurs frequently. For instance, if you receive a bill which indicates payment is due Net 30 from the invoice date, the due date is generally 30 calendar days (unless otherwise noted). Likewise, a 15 day free trial typically starts on the date it is activated, and terminates 15 days later.

You can also calculate dates using business days, by setting Business Days Only? to Yes. When days are subtracted or added using business days, the weekend days (Saturday and Sunday) are ignored and not part of the count. For example, if it is currently Monday November 1, 2021, adding 15 business days will occur on Monday November 22, 2021. There are actually 3 full weekends in this calculation (3 Saturdays and 3 Sundays), all of which are excluded from the business day date math. With calendar days, the calculated date would be Tuesday November 16, 2021 since weekends are included.

Note: This calculator does not currently take into account federal holidays, which means they are included when adding or subtracting days. Therefore, if federal holidays occur from your base date to the calculated date and you do not want included, you'll need to adjust the calculated date manually.

Adding and Subtracting Days Examples

Certificates of Deposit (CD) - Most CDs have a fixed duration, such as 3 months (90 days), 6 months (180 days), etc. At the end of that period, on the maturity date, the CD often automatically rolls over, or you can close it, change the term, or withdraw without penalty. When the CD reaches its term, you often have a 7 to 10 day grace period to decide what action you will take. The grace period can be based on calendar days, or business days, depending on the bank's policy. The days calculator makes it easy to calculate the maturity date of a CD, as well as the date on which the grace period expires.

Temporary Car Registration and Driver's Licenses - In the USA, each state varies regarding how long a temporary registration or license is valid; In some states, for example, it's 30 days, while in others 45 days or 60 days. The days calculator can calculate expiration dates, using the initial date and number of days.

First Date, Second Date Dependent Events - Anytime you have two connected events, where the second should occur a certain number of days after the first, the days calculator can easily calculate the second date. Covid-19 vaccinations which were two-part are an example: depending on the vaccine, the second shot was to occur 21 days (Pfizer) or 28 days (Moderna) after the first.

IRA Roll Over - Per the IRS, one has 60 days from the date an IRA distribution is received to roll it over into another plan. Calculating that date is simple with the days calculator: enter date distribution received, 60 days, and calculate with calendar days.

Seasons Come and Go - If you're located in snow country, and have a bit of cabin fever, the days calculator is a fun way to daydream seasons! Will it be Spring 30 days from now, 70 days? Where were you 100 days ago (subtract 100 calendar days from today)? Likewise, if you can not wait for the dog days of Summer to fade away...

When to Use Business Days or Calendar Days

The days date calculator will use calendar days in the calculation unless you opt for Business Days. But when should you use business days or calendar days? This depends on what you are calculating, so it's application dependent; You should check with whomever is setting the rules.

For example, in the case of CD roll over grace periods, both the number of days comprising the grace period and whether that grace period is calculated using business days or calendar days is based on a financial institution's policies. Some banks not only define short grace periods based on business days, but also include federal holidays in that count, thereby providing consumers with very small time windows to make decisions.