I frequently have to export data from a layer in ArcGIS online (that is created from Arc Collector offsite) to excel via CSV format. One of the fields is the CreationDate field that is automatically created when a layer is used. Every time I download the layer and export to excel, the time is always incorrect: seven hours are added to each correct time. For example, a time in excel reads 21:30 when it should read 14:30. The time zone and format for all equipment used is the same, so I am not sure what is happening when the data is exported.
The time output is in UTC which is the time the database is in. UTC is the basis for local times worldwide and is the default used in geodatabases and in the databases hosted data from ArcGIS Online is in.
And this post in quora can help you convert the time to your timezone in excel
Just a simple math equation and remember to have your field set as date or it will automatically format it as a numeric field.