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Daylight Saving Time

This data service calculates the start and end dates for Daylight Saving Time in the U.S. for 1967 and later. Enter a year below and click on the "Get Data" button.


Year For example: 1986


Notes

At the start date of Daylight Saving Time, the clock is advanced by one hour; at the end date of Daylight Saving Time, the clock is decreased by one hour.

Not all places in the U.S. observe Daylight Saving Time. Hawaii and most of Arizona observe standard time only.

For information about the implementation and history of Daylight Saving Time in the U.S., go here.

Application Programming Interface

This data service uses one of our Application Programming Interfaces (APIs). The API returns data in JavaScript Object Notation (JSON) format for users who wish to manipulate data into a customized format. For more information on the API, please see the documentation page.