Please Note: This article is written for users of the following Microsoft Excel versions: 2007, 2010, 2013, and 2016. If you are using an earlier version (Excel 2003 or earlier), this tip may not work for you. For a version of this tip written specifically for earlier versions of Excel, click here: Converting Mainframe Date Formats.

Converting Mainframe Date Formats

by Allen Wyatt
(last updated July 7, 2018)

Some of the data you work with in Excel may start as output from large systems in your office. Sometimes the date formats used by the large systems may be completely misunderstood by Excel. For instance, the output may provide dates in the format yyyydddtttt, where yyyy is the year, ddd is the ordinal day of the year (1 through 366), and tttt is the time based on a 24-hour clock. At first glance, you may not know how to convert such a date to something that Excel can use.

There are many ways that a solution could be approached. Perhaps the best formula, however, is the following:

=DATE(LEFT(A1,4),1,1)+MID(A1,5,3)-1+TIME(MID(A1,8,2),RIGHT(A1,2),0)

This formula first figures out the date serial number for January 1 of the specified year, then adds the correct number of days to that date. The formula then calculates the right time based on what is provided.

When a formula like this is invoked, the result is a date serial number. This means that the cell still needs to be formatted to display a date format.

This approach will work just fine, provided that the information that you start with makes sense. For instance, you will always get the expected result if ddd really is within the range of 1 through 366, or if tttt is a properly formatted 24-hour representation of time. If you anticipate original data that could be out of bounds, then the best solution is to create a custom function (using a macro) that will tear apart the original data and check the values provided for each portion. If the data is out of bounds, the function could return an error value that would be easily detected within the worksheet.

ExcelTips is your source for cost-effective Microsoft Excel training. This tip (9241) applies to Microsoft Excel 2007, 2010, 2013, and 2016. You can find a version of this tip for the older menu interface of Excel here: Converting Mainframe Date Formats.

Author Bio

Allen Wyatt

With more than 50 non-fiction books and numerous magazine articles to his credit, Allen Wyatt is an internationally recognized author. He is president of Sharon Parq Associates, a computer and publishing services company. ...

MORE FROM ALLEN

Changing AutoFormatting Rules

The AutoFormat feature of Word can be configured to make changes to a variety of conditions in your document. Here's how ...

Discover More

Hanging When Opening a Workbook

If you are opening a workbook and Excel seems to hang without ever fully loading, it could be due to a number of ...

Discover More

Pulling Filenames into a Worksheet

You can use Excel for all types of data processing. You may want to work with filenames in a worksheet, but the first ...

Discover More

Save Time and Supercharge Excel! Automate virtually any routine task and save yourself hours, days, maybe even weeks. Then, learn how to make Excel do things you thought were simply impossible! Mastering advanced Excel macros has never been easier. Check out Excel 2010 VBA and Macros today!

More ExcelTips (ribbon)

Calculating a Group Retirement Date

Calculating a retirement date can be as simple as doing some date math to see when a person reaches a certain age. ...

Discover More

Backwards Date Parsing

Enter information into a worksheet, and you come to anticipate (and count on) how Excel will interpret that information ...

Discover More

Month for the Nth Sunday

Doing math with dates is quite easy in Excel. As this tip illustrates, this fact makes it easy to figure out the Nth ...

Discover More
Subscribe

FREE SERVICE: Get tips like this every week in ExcelTips, a free productivity newsletter. Enter your address and click "Subscribe."

View most recent newsletter.

Comments

If you would like to add an image to your comment (not an avatar, but an image to help in making the point of your comment), include the characters [{fig}] in your comment text. You’ll be prompted to upload your image when you submit the comment. Maximum image size is 6Mpixels. Images larger than 600px wide or 1000px tall will be reduced. Up to three images may be included in a comment. All images are subject to review. Commenting privileges may be curtailed if inappropriate images are posted.

What is 3 + 4?

There are currently no comments for this tip. (Be the first to leave your comment—just use the simple form above!)


This Site

Got a version of Excel that uses the ribbon interface (Excel 2007 or later)? This site is for you! If you use an earlier version of Excel, visit our ExcelTips site focusing on the menu interface.

Newest Tips
Subscribe

FREE SERVICE: Get tips like this every week in ExcelTips, a free productivity newsletter. Enter your address and click "Subscribe."

(Your e-mail address is not shared with anyone, ever.)

View the most recent newsletter.