Posts: 107
Registered: ‎04-04-2016

Converting JSON to Date/Time



Trying to convert a 13 digit JSON date column to date/time. In Edit Query I change my JSON column,["Column1.Date - Copy"] to whole number.

I get 1.45731E+12 (1 example). I create a custom column and use this formula -> = ([#"Column1.Date - Copy"]/1000+7200)/84600+25569. I get 42794.95745.

When I change the column format to Date/Time I get 28/02/2017 10:58am. This should be 07/03/2016.


Any ideas what I'm doing wrong?



Senior Member
Posts: 252
Registered: ‎12-07-2015

Re: Converting JSON to Date/Time

Posts: 107
Registered: ‎04-04-2016

Re: Converting JSON to Date/Time



Thanks for the reply. I have zero knowledge of PQFL. In Curt's code what do I need to change to 

make it applicable to me? Is the let Json.Date the column that contains the JSON date in my table?



Frequent Visitor
Posts: 12
Registered: ‎10-02-2015

Re: Converting JSON to Date/Time

Let's try this way



The step to execute to do the transformation

= Table.TransformColumns(#"<previous step name>",{{"<column name to update>", DateFromJson}})

The code of the Power Query custom function (create a new Query and post this code as it is)

let DateFromJson = (date as any) as any =>
        input = if date is null then "/Date(00000000000000)/"else date,
         Stripped = if Text.StartsWith(input, "/Date(") and Text.EndsWith(input, ")/") then Text.Range(input, 6, Text.Length(input) - 8) else error "Not a date",
         Position = Text.PositionOfAny(Stripped, {"+", "-"}, 1),
         Parts = if Position < 0 then { Stripped, "0" } else { Text.Range(Stripped, 0, Position), Text.Range(Stripped, Position) },
         NumberParts = { Number.FromText(Parts{0}), Number.FromText(Parts{1}) },
         Result = Date.FromText("1/1/1970") + #duration(0, 0, 0, (NumberParts{0} + 36000 * NumberParts{1}) / 1000),
        output = if Date.Year(Result) = 1970 then null else Result

 in DateFromJson


Frequent Visitor
Posts: 7
Registered: ‎04-07-2017

Re: Converting JSON to Date/Time

In case anyone else needs a simpler solution, this is what worked for me.


#"Add Column" = Table.AddColumn(#",Previous Step Name", "<new column name>", each (#datetime(1970, 1, 1, 0, 0, 0 ) + #duration(0, 0, 0, [<field to change>]+36000/1000))),