I did a few searches for Omnigraffle date time format and didn’t find any conclusive results. So I created block of test code containing every letter of the alphabet and then used the search results to document each code. There were a few I wasn’t 100% sure of, so please leave a comment if you know more.
Examples
To get Last modified on Friday, September 4 at 01:42 AM, use:
Last modified on <%ModificationDate %A, %B %e at %I:%M %p %>
To get 2005-10-07 01:48, use:
<%Date %Y-%m-%d %H:%M%>
To get Oct 07, 2005, use:
<%Date %b %d, %Y%>
General Codes
%c
Preferred local format
<%Date %c%> Fri Sep 04 01:50:02 US/Pacific 2009
%x
The language-aware standard date representation.
<%ModificationDate %x %> Thu Sep 03 2009%X
The language-aware time representation.
<%ModificationDate %X %> 15:36:49 US/Pacific
Time Codes
%I
The two-digit hour on a 12-hour clock padded with a zero if applicable.
<%ModificationDate %I %> 03%i
Seems to be an alias of %I (Halp?)
%H
The two-digit 24-hour clock padded with a zero if applicable.
<%ModificationDate %H %> 16%M
The two-digits minute padded with a leading zero if applicable.
<%ModificationDate %M %> 02%S
The two-digit second padded with a zero if applicable.
<%ModificationDate %S %> 04%p
Either AM or PM. Language dependent.
<%ModificationDate %p %> AM%F
Three digit miliseconds, range from 000 to 999.
<%ModificationDate %F %> 845%Z
Time zone.
<%Date %Z%> US/Pacific%z
Timezone offset.
<%Date %z%> -0700
Date Codes
%A
The full weekday name.
<%ModificationDate %A %> Thursday%a
The abbreviated weekday name.
<%ModificationDate %a %> Thu%B
The full month name.
<%ModificationDate %B %> September%b
The abbreviated month name.
<%ModificationDate %b %> Sep%m
The two-digit month padded with a leading zero if applicable.
<%ModificationDate %m %> 09%e
The day of the month.
<%ModificationDate %e %> 9%Y
The four-digit year.
<%ModificationDate %Y %> 2009%y
The two-digit year padded with a leading zero if applicable.
<%ModificationDate %y %> 01%j
The three-digit day of the year (ranging from 000 to 364) padded with leading zeroes if applicable.
<%ModificationDate %j %> 040%w
The numeric day of the week ranging from 0 to 6 where 0 is Sunday.
<%ModificationDate %w %> 0
Testing Code
a: <%ModificationDate %a %> A: <%ModificationDate %A %>
b: <%ModificationDate %b %> B: <%ModificationDate %B %>
c: <%ModificationDate %c %> C: <%ModificationDate %C %>
d: <%ModificationDate %d %> D: <%ModificationDate %D %>
e: <%ModificationDate %e %> E: <%ModificationDate %E %>
f: <%ModificationDate %f %> F: <%ModificationDate %F %>
g: <%ModificationDate %g %> G: <%ModificationDate %G %>
h: <%ModificationDate %h %> H: <%ModificationDate %H %>
i: <%ModificationDate %i %> I: <%ModificationDate %I %>
j: <%ModificationDate %j %> J: <%ModificationDate %J %>
k: <%ModificationDate %k %> K: <%ModificationDate %K %>
l: <%ModificationDate %l %> L: <%ModificationDate %L %>
m: <%ModificationDate %m %> M: <%ModificationDate %M %>
n: <%ModificationDate %n %> N: <%ModificationDate %N %>
o: <%ModificationDate %o %> O: <%ModificationDate %O %>
p: <%ModificationDate %p %> P: <%ModificationDate %P %>
q: <%ModificationDate %q %> Q: <%ModificationDate %Q %>
r: <%ModificationDate %r %> R: <%ModificationDate %R %>
s: <%ModificationDate %s %> S: <%ModificationDate %S %>
t: <%ModificationDate %t %> T: <%ModificationDate %T %>
u: <%ModificationDate %u %> U: <%ModificationDate %U %>
v: <%ModificationDate %v %> V: <%ModificationDate %V %>
w: <%ModificationDate %w %> W: <%ModificationDate %W %>
x: <%ModificationDate %x %> X: <%ModificationDate %X %>
y: <%ModificationDate %y %> Y: <%ModificationDate %Y %>
z: <%ModificationDate %z %> Z: <%ModificationDate %Z %>
