# Date Duration Calculator

Reset

## What date/time formats do you support?

We support a wide variety of date/time formats. Here are a few examples:

`2012`
`Jan 2012`
`Jan 4, 2012`
`Jan 4, 2012 4pm`
`Jan 4, 2012 4:20pm`
`Jan 4, 2012 4:20:45pm`
`Jan 4, 2012 16:20:45`

`January 4, 2012`

`4/1/2012`
`4/1/2012 4pm`

`4-1-2012`
`4-1-2012 4pm`

`4 Jan 2012`
`4 Jan 12`

`24 AD`
`24 CE`
`24 BC`

`Present`

A few notes:

• Commas are optional
• If you just enter a year, the calculator will assume you mean Jan 1 of that year.
• If you enter a year and a month, the calculator will assume you mean the first day of the month.
• If you enter a date without a time, the calculator will assume you mean the beginning of the calendar day.
• You can abbreviate the name of the month.
• If you use 00-29 as the year, the calculator will assume you mean 2000-2029. If you use 30-99, it assumes 1930-1999.
• If you want to actually use the year 00 to 99, add “AD” or “CE” to the end of it.
• You cannot specify months and days for BC years (years before 0).
• If you use the slash format for the dates, it assumes you mean month/day/year. This is important because in many countries the format is day/month/year.

The calculator will show you the exact date/time it used in the results so you can double-check it to make sure it used the date you wanted.

## How do I use the present date/time?

Enter `Present` when you want the calculator to use the current date.

For example, if you want to know how long it is until 2050, you could enter `Present` as the start date and `2050` as the end date.

If you want to know how long it’s been since VE Day, for example, enter `May 8, 1945` as the start date and `Present` as the end date.

## How can I figure out how old I am?

Enter your birthday as the start date and `Present` as the end date.

## Why do you show two different durations for some searches?

If you use an end date without a time, the Date to Date Calculator will show one duration that includes that end date and one that doesn’t.

For example, let’s say you enter `Jan 1, 2012` as the start date and `Jan 3, 2012` as the end date. The calculator will show “Duration not including end date: 2 days” and “Duration including end date: 3 days”. Why?

When some people search for this, they’ll mean Jan 1 to the start of Jan 3 and other people will mean Jan 1 to the end of Jan 3. Since we can’t know your intentions when you enter a date like this, we’ll show you one result that includes Jan 3 and another that doesn’t. You can use whichever result applies to your situation.

## What is this site?

The Date to Date Calculator is part of Preceden, an online timeline maker that lets you create simple, multilayered timelines. If you like the Date to Date Calculator, you’ll love Preceden. Get started on the Preceden homepage.