I had a same question today and I found some CSV rules.
Marketo CSV datetime rules.
- CSV datetime format has to be yyyy-mm-dd hh:mm:ss or yyyy-mm-dd hh:mm
if you use date separater '/', Date has to be m/d/yyyy order. See Import Members from a Spreadsheet into a Program - Marketo Docs - Product Docs
If it is not m/d/yyyy order, Datetime will not be correct. eg. 2015/6/1 => Jan. 6th 2015
- CSV datetime has to be UTC-5
We have to create a new column and calculate UTC-5.
For example, when I'm working in Japan(UTC+9). I have to create a column(-14hour).
- UTC and GMT format are not supported.
12:34:56+9:00 =>NG
12:34:56 GMT+9:00 =>NG
Will it always be UTC-5 even in daylight savings?
UTC-5 is EST during standard time, but CT during daylight savings. I just wonder if they expect EST instead, which would be UTC-5 or UTC-4 depending on whether daylight savings in the USA.
Yes, always.
It seems marketo internal clock is utc-5 always.
Almost marketo UI is supported user timezone.
But if you use api's, i recommend you remember this rule.
Now W3C Date and Time Formats is supported as Kenny Elkington said
It's a great change.
You should use W3C formatted datetimes whenever possible: YYYY-mm-ddThh:mm:ssz for UTC or YYY-m-dThh:mm:ss-00:00 with an offset.
This is what I do for API calls, but the W3C formats don't work for CSV imports. If I send a datetime like "2015-11-11T16:07:38+00:00" within a csv, it gets set to "2015-11-11 00:00:00".