--- title: Improved timezone handling in the API author_name: dbussink --- We have improved support for handling timezones in our API. For example, if you create commits through the API, we now allow for specifying timezone information more accurately. We apply the following rules, in order of priority, to determine timezone information for API calls: #### Explicitly provide an ISO 8601 timestamp with timezone information For API calls that allow for a timestamp to be specified, we use that exact timestamp. An example of this is the [Commits API](/v3/git/commits) which allows for specifying the `date` property. <%= json "message"=> "my commit message", \ "author"=> \ {"name" => "Dirkjan Bussink", "email" => "d.bussink@gmail.com", \ "date" => "2014-02-27T15:05:06+01:00"}, \ "parents"=>["7d1b31e74ee336d15cbd21741bc88a537ed063a0"], \ "tree"=>"827efc6d56897b048c772eb4087f854f46256132" %> #### Using the `Time-Zone` header It is possible to supply a `Time-Zone` header which defines a timezone according to the [list of names from the Olson database](https://en.wikipedia.org/wiki/List_of_tz_database_time_zones). ``` command-line $ curl -H "Time-Zone: Europe/Amsterdam" -X POST https://api.github.com/repos/github/linguist/contents/new_file.md ``` This means that we generate a timestamp for the moment your API call is made in the timezone this header defines. For example, the [Contents API](/v3/repos/contents/) generates a git commit for each addition or change and uses the current time as the timestamp. This header will determine the timezone used for generating that current timestamp. #### Using the last known timezone for the user If no `Time-Zone` header is specified and you make an authenticated call to the API, we use the last known timezone for the authenticated user. The last know timezone is updated whenever you browse the GitHub.com website. #### UTC If the steps above don't result in any information, we use UTC as the timezone to create the git commit. If you have any questions or feedback, don't hesitate to [contact] us! [contact]: https://github.com/contact?form[subject]=API+timezones