Date Time Difference Calculator

Date Calculator: Add to or Subtract From a Date

The Date Calculator lets you add or subtract days, weeks, months, and years to or from a given date to calculate a past or future date.

Calculates the duration between two dates. This calculator calculates the duration, which is the day count and the number of days, months and years between two dates.

Popular uses for our date duration calculator

• Calculate time worked with company
• How many days since I was born
• Figure out how long ago someone was alive
• Use in financial mathematics course
• On what day was I born
• How many days since...
• Project Planning & Lead Time estimating
• Time Management
• Financial forecasting
• Medical timing as in pregnancy due dates
• Commonly used in the Automotive, Construction, and Medical Industries
• Track when shipments are due to arrive
• Calculate how long something is overdue
• Find the day of the week for any past, present, or future date
• Calculate the Julian date of any day by setting the start date to 12/31

When should you use the Add/Subtract Days Calculator, and how should you use it?

You can use the date duration calculator in a variety of ways. Here are a few examples of using the date calculator and when to utilize it.

Calculate the number of days till something expires.

Whether it's a free trial or a subscription, use this add/subtract days calculator to track when it expires. Simply input the start date (which in this case refers to the beginning of the product subscription) and the number of days (which refers to the duration of the subscription).

For example, if you have a free trial for Office 365 services and want to know when it ends, input the start date of your subscription and the number of days left on the trial. After that, you'll receive the date's specifics.

Determine your project's time frame.

This add/subtract days calculator can help you create your client's invoice if you're working on a project (like freelancers or independent contractors). The date range is usually included in most invoice layouts. If an invoice is sent every two weeks, add 14 days (including weekends) to the invoice's start date to get the invoice's end date. That will bring the invoice's date span to a close.

Establish a deadline for something.

This add/subtract days calculator helps determine when a specific account payment or receivable is due. This can be useful for freelancers or independent contractors that want to include the invoice due date based on Net15 or Net30. If you're going to specify a specific date, multiply the number of days by the number of days you want. (based on contract).