This Elm package contains time zone data from the IANA Time Zone Database for using with elm/time.

The elm/time library provides a Posix type for representing an instant in time. Extracting human-readable parts from a Posix time requires a Time.Zone. This library provides Time.Zone values for all named zones in the database, covering changes between 1970 and 2037.

elm install justinmimbs/timezone-data

The TimeZone.getZone task gets the client's local Time.Zone along with its zone name.

import Time
import TimeZone

getZone : Task TimeZone.Error ( String, Time.Zone )
getZone =
    TimeZone.getZone

See this page for a full example.

Each zone is stored as a function, waiting to be evaluated to a Time.Zone.

import Time
import TimeZone exposing (america__new_york)


-- unevaluated

lazyZone : () -> Time.Zone
lazyZone =
    america__new_york


-- evaluated

zone : Time.Zone
zone =
    america__new_york ()

Once evaluated, you should store the Time.Zone values you need in your model so that they don't need to be evaluated again.

Using this library to include all time zones in your compiled asset would increase its minified and gzipped size by about 18 KB. For a more lightweight approach to getting time zones into Elm, you may consider fetching only the data you need at runtime. And if your use case is taking UTC timestamps and displaying them nicely formatted in the client's local time, then you may look into custom elements, like Github's time-elements.