ISO
8601:2000(E)
©
ISO
2000
All
rights
reserved
11
[Y]
[M]
[W]
[D]
[H]
[M]
[S]
NOTE
In
these
representations,
[M]
may
be
used
to
indicate
"month"
or
"minute",
or
both.
5.2
Dates
For
ease
of
comparison,
in
all
the
following
examples
of
representations
of
dates,
the
date
of
12
April
1985
is
used
as
an
illustration,
as
applicable.
5.2.1
Calendar
date
In
expressions
of
calendar
dates
¾
day
of
the
month
(calendar
day)
is
represented
by
two
digits.
The
first
day
of
any
month
is
represented
by
[01]
and
subsequent
days
of
the
same
month
are
numbered
in
ascending
sequence;
¾
month
is
represented
by
two
digits.
January
is
represented
by
[01],
and
subsequent
months
are
numbered
in
ascending
sequence;
¾
year
is
generally
represented
by
four
digits;
years
are
numbered
in
ascending
order
according
to
the
Gregorian
calendar
by
values
in
the
range
[0000]
to
[9999].
Values
in
the
range
[0000]
through
[1582]
shall
only
be
used
by
mutual
agreement
of
the
partners
in
information
interchange.
5.2.1.1
Complete
representation
When
the
application
identifies
the
need
for
an
expression
only
of
a
calendar
date,
then
the
complete
representation
shall
be
a
single
numeric
data
element
comprising
eight
digits,
where
[YYYY]
represents
a
calendar
year,
[MM]
the
ordinal
number
of
a
calendar
month
within
the
calendar
year,
and
[DD]
the
ordinal
number
of
a
day
within
the
calendar
month.
Basic
format:
YYYYMMDD
EXAMPLE
19850412
Extended
format:
YYYY-MM-DD
EXAMPLE
1985-04-12
5.2.1.2
Representations
with
reduced
precision
If
in
a
given
application
it
is
sufficient
to
express
a
calendar
date
with
less
precision
than
a
complete
representation
as
specified
in
5.2.1.1,
either
two,
four
or
six
digits
may
be
omitted,
the
omission
starting
from
the
extreme
right-hand
side.
The
resulting
representation
will
then
indicate
a
month,
a
year
or
a
century,
as
set
out
below.
When
only
[DD]
is
omitted,
a
separator
shall
be
inserted
between
[YYYY]
and
[MM],
but
separators
shall
not
be
used
in
the
other
representations
with
reduced
precision.
a)
A
specific
month
Basic
format:
YYYY-MM
EXAMPLE
1985-04
Extended
format:
not
applicable
b)
A
specific
year
Basic
format:
YYYY
EXAMPLE
1985
Extended
format:
not
applicable
c)
A
specific
century
Basic
format:
YY
EXAMPLE
19
Extended
format:
not
applicable
