W3C
Editor's
Draft
10
July
Copyright © 2018-2025 World Wide Web Consortium . W3C ® liability , trademark and permissive document license rules apply.
This document describes or points to requirements for the layout and presentation of text in languages that use the Traditional Mongolian script. The target audience is developers of Web standards and technologies, such as HTML, CSS, Mobile Web, Digital Publications, and Unicode, as well as implementers of web browsers, ebook readers, and other applications that need to render Mongolian text.
This section describes the status of this document at the time of its publication. A list of current W3C publications and the latest revision of this technical report can be found in the W3C standards and drafts index .
This document describes the basic requirements for Mongolian script layout and text support on the Web and in eBooks. These requirements provide information for Web technologies such as CSS, HTML and digital publications about how to support users of Mongolian script languages. Currently the document focuses on the Traditional Mongolian script as used for Mongolian. The information here is developed in conjunction with a document that summarises gaps in support on the Web for Mongolian.
The editor's draft of this document is being developed by the Mongolian Layout Task Force , part of the W3C Internationalization Interest Group . It is published by the Internationalization Working Group . The end target for this document is a Working Group Note.
To make it easier to track comments, please raise separate issues or emails for each comment, and point to the section you are commenting on using a URL.
This document was published by the Internationalization Working Group as an Editor's Draft.
Publication as an Editor's Draft does not imply endorsement by W3C and its Members.
This is a draft document and may be updated, replaced, or obsoleted by other documents at any time. It is inappropriate to cite this document as other than a work in progress.
This document was produced by a group operating under the W3C Patent Policy . W3C maintains a public list of any patent disclosures made in connection with the deliverables of the group; that page also includes instructions for disclosing a patent. An individual who has actual knowledge of a patent that the individual believes contains Essential Claim(s) must disclose the information in accordance with section 6 of the W3C Patent Policy .
This document is governed by the 03 November 2023 W3C Process Document .
Some links on this page point to repositories or pages to which information will be added over time. Initially, the link may produce no results, but as issues, tests, etc. are created they will show up.
Links that have a gray color led to no content the last time this document was updated. They are still live, however, since relevant content could be added at any time. When the document is updated, links that now point to results will have their live colour restored.
The original text of this document was prepared by Nasun-urt and Hu Chitu. Richard Ishida reorganised the material and added the script overview.
See also the GitHub contributors list for the Mongolian Language Enablement project, and the discussions related to Traditional Mongolian script .
The aim of this document is to describe the basic requirements for Traditional Mongolian script layout and text support on the Web and in eBooks. These requirements provide information for Web technologies such as CSS, HTML and digital publications, and for application developers, about how to support users of the Mongolian script. The document currently focuses on texts using the Mongolian language.
The main purpose of this document is to provide standardization and guiding rules for the display and application of traditional Mongolian script in the web. However, the more complex layout requirements such as paper layout are not included in this document. Thus, this document includes the most basic rules of display of page and characters of the traditional Mongolian script, aiming at formulating the corresponding standards of web display and application of Mongolian script for the web application vendors to follow this standard of display and application of Mongolian script in the web.
The following terms and definitions apply to this standard.
This document is pointed to by a separate document, Mongolian Gap Analysis , which describes gaps in support for Mongolian on the Web, and prioritises and describes the impact of those gaps on the user.
Wherever an unsupported feature is indentified through the gap analysis process, the requirements for that feature need to be documented. The gap reports will typically point back to this document for more information.
As gaps in support for Mongolian are captured, the gaps can be brought to the attention of the relevant spec developer or the browser implementator community. The progress of such work is tracked in the Gap Analysis Pipeline .
This document should contain no reference to a particular technology. For example, it should not say "CSS does/doesn't do such and such", and it should not describe how a technology, such as CSS, should implement the requirements. It is technology agnostic, so that it will be evergreen, and it simply describes how the script works. The gap analysis document is the appropriate place for all kinds of technology-specific information.
To complement any content authored specifically for this document, the sections in the document also point to related, external information, tests, GitHub discussions, etc.
The document Language enablement index points to this document and others, and provides a central location for developers and implementers to find information related to various scripts.
The W3C also has a repository with discussion threads related to the Mongolian script, including requests from developers to the user community for information about how scripts/languages work, and a notification system that tracks issues in W3C working groups related to the Mongolian script. See a list of unresolved questions for Mongolian experts. Each section below points to related discussions. See also the repository home page .
The Mongolian script is an alphabet , ie. a writing system in which both consonants and vowels are indicated.
Modern Mongolian can be written using a subset of the letters available in the Mongolian Unicode block. The remainder are used for writing Todo, Sibe, and Manchu, or for writing foriegn words, especially in Tibetan and Sanskrit.
Mongolian text runs top to bottom in vertical lines and (unusually) the lines flow left to right .
The script is cursive , ie. letters in a word are joined. All letters join both on the left and right.
Words are separated by spaces, but also contain narrow spaces that precede suffixes and may produce shaping differences to the surrounding letters. These are part of the word, and the parts on either side should not be separated.
Modern Mongolian uses 16 basic consonant letters and 11 more for representing foreign sounds.
In the Traditional Mongolian alphabet vowels are written using 8 vowel letters, including one for foreign sounds.Mongolian has separate code points for each sound in Mongolian, but many of these look indistinguishable from each other when rendered. This creates difficulties for novices to reproduce Mongolian text without access to the source.
Vowel reduction is a significant feature of Mongolian. Non-initial short vowels are reduced to vestiges or to zero, and non-initial long vowels in the orthography are reduced to short vowel length.
Vowel harmony is another key feature, grouping vowels in a way that indicates a front or back position for the tongue root (ATR).
The script is monocameral.
There is a set of Mongolian digits.
The Mongolian writing direction is shown in Figure 1 .
Traditionally, Mongolian does not have the concept of italics, and it is not used in modern times either. When it becomes necessary to synthesize an italic typeface, the text should tilt downward in a clockwise direction for vertical text and to the right in a clockwise direction for horizontal text.
Mongolian word suffixes are separated from the preceding word using U+202F NARROW NO-BREAK SPACE , rather than U+0020 SPACE . For example, the code points that make up the suffix “ ᠤᠨ ” are: 0x202F 0x1824 0x1828.
U+202F NARROW NO-BREAK SPACE and a following suffix cannot appear at the beginning of a line. For example, Figure 3 shows the correct approach and Figure 4 shows an incorrect approach.
Inline selected text must overlap the Mongolian baseline, as shown in Figure 5 . Multi-line selection must follow the writing direction of the Mongolian script, i.e., text direction from top to bottom and from left to right, as shown in Figure 6 .
Striking cursor movement keys on the keyboard, including “←”, “→”, “↑”, “↓”, “Page Up”, “Page Down”, “Home” and “End”, should produce movement that follows the writing direction of the Mongolian script from top to bottom and from left to right. For example, the cursor moves to the left after striking the “←” key; the cursor moves to the right when striking the “→” key. The cursor moves down after striking the “↓” key. When the cursor reaches the bottom of the current line, and the key “↓” is pressed again, the cursor will move right and to the top of the next line, as shown in Figure 7 . In the case of the “↑” key, the opposite occurs.
The mouse pointer in text editing is shown in Figure 8 .
The scrollbar will scroll left and right when mouse wheel is scrolling, that is, the scrollbar will move left or the text will move right when mouse wheel is scrolling forward; the scrollbar will move right or the text will move left when mouse wheel is scrolling backward.
The cursor shape during text editing (shown in Figure 8 ) must be aligned at the base on the midpoint of the Mongolian script baseline, that is, the midpoint of the Mongolian script baseline overlaps the midpoint of the cursor, with the length no longer than the middle line between the two lines of the text, as shown in Figure 9 .
Mongolian has some specific requirements related to punctuation:
Mongolian names of Mongolian punctuation and writing direction are as shown in Figure 10 , namely the writing direction is the same as that in the graph. Need to clarify the meaning of this bullet.
Mongolian punctuation should be centered vertically, as shown in Figure 11 .
The “right line” in Mongolian writing is to the right of the text, and is used similarly to the underline of horizontal English and Chinese text. The “left line” is to the left of the text, and is used similarly to the overline of horizontal English and Chinese text. The strikethrough is a baseline-centered vertical line as shown in Figure 12 .
Underline, overline and strikethrough in mixed composition with other languages are shown in Figure 13 :
Lines alongside the text may break on the spaces between words. When doing so, the gaps introduced before suffixes by U+202F NARROW NO-BREAK SPACE and U+180E MONGOLIAN VOWEL SEPARATOR should not be skipped. Even though there is a gap, suffixes are considered part of the word. See an example in the second word of Figure 14 :
Due to the different height of Mongolian text, in order to ensure that every character is in fully displayed and the whole word looks beautiful, the height of each letter must keep in balance. The spaces between words must be different from the common gaps before suffixes, whose code point is U+202F NARROW NO-BREAK SPACE . See Figure 15 :
In Mongolian, emphasis is typically expressed by either changing the font or drawing a wavy line. For horizontal text, the wavy line is placed beneath the text, while for vertical text, it appears on the right side. Mongolian does not use italics to indicate emphasis. §
Line-breaking
should
not
split
words.
Figure
16
shows
correct
line-breaking,
without
breaking
the
Mongolian
words.
Figure
17
shows
incorrect
line-breaking
for
“
”
and
“
”.
Spacing can be added to the first line of a paragraph for indentation. There is no clear standard for how much indentation to use.
Text
alignment
includes
"left
alignment",
"horizontal
centering",
and
“right
alignment
”,
"right
alignment",
as
well
as
“top
alignment”,
“vertical
centering”,
“bottom
alignment”and
“top-bottom
alignment”.
"top
alignment",
"vertical
centering",
"bottom
alignment",
and
"top-bottom
alignment".
"Left
alignment
",
alignment",
"horizontal
centering"
centering",
and
“right
alignment”
"right
alignment"
are
the
alignment
rules
that
apply
inside
a
line.
“Top
alignment”,
“horizontal
centering”,
“bottom
alignment”
"Top
alignment",
"vertical
centering",
"bottom
alignment",
and
“top-bottom
alignment”
"top-bottom
alignment"
are
the
alignment
rules
in
a
page
or
a
paragraph
of
a
multi-line
text.
Among
"left
alignment",
"horizontal
centering"
centering",
and
“right
alignment”,
“horizontal
centering”
"right
alignment",
"horizontal
centering"
is
a
the
default
option
option,
which
means
that
the
Mongolian
text
will
align
based
on
its
baseline
axis.
“Left
alignment”
"Left
alignment"
means
that
the
text
will
move
be
positioned
to
the
left
by
a
certain
distance,
which
shows
obvious
differences
compared
with
the
text
after
setting
“horizontal
center”.
“Right
alignment”
"horizontal
center".
"Right
alignment"
means
that
the
text
will
move
be
positioned
to
the
right
by
a
certain
distance
after,
distance,
which
shows
obvious
differences
compared
with
the
text
after
setting
“horizontal
center”.
"horizontal
center".
Among
“Top
alignment”,
“vertical
center”,
“bottom
alignment”
"top
alignment",
"vertical
centering",
"bottom
alignment",
and
“top-bottom
alignment”,
“top-bottom
alignment”
"top-bottom
alignment",
"top-bottom
alignment"
is
a
the
default
option
option,
which
means
that
the
words
in
at
both
the
upper
and
the
lower
boundary
boundaries
of
a
multi-line
text
in
a
paragraph
or
a
page
are
all
aligned.
Its
This
alignment
method
is
that
stretches
the
spaces
in
the
text
are
stretched
in
the
same
proportion.
“Top
alignment”
proportionally.
"Top
alignment"
means
that
the
words
in
at
the
upper
boundary
of
a
multi-line
text
in
a
paragraph
or
a
page
are
all
aligned
without
considering
the
alignment
of
the
lower
boundary
and
or
stretching
the
space
between
words.
“Vertical
center”
"Vertical
center"
means
the
words
in
at
the
upper
and
the
lower
boundary
boundaries
of
a
multi-line
text
in
a
paragraph
or
a
page
do
not
need
to
align
and
leave
equal
spacing
without
stretching
the
same
blank
under
the
condition
of
no-stretching
space
between
words.
Mongolian
is
aligned
to
a
baseline
that
runs
down
the
center
of
the
writing,
and
all
text
is
aligned
to
this
baseline
as
shown
in
Figure
18
19
:
When mixed with other languages, the text in those languages should also be centre-aligned along the Mongolian baseline.
There
is
no
obvious
midcourt
line
in
numbers
and
Latin.
Therefore
generally,
half
of
the
text
height
is
regarded
as
a
midcourt
line
position.
When
Mongolian
script
is
mixed
with
numbers
and
Latin,
the
line
of
half
of
the
text
height
should
be
aligned
with
Mongolian
midcourt
line.
When
font
size
of
numbers
is
the
same
as
Mongolian’s,
it
will
be
slightly
larger,
so
some
handling
methods
should
be
taken
to
avoid
the
problem,
such
as
the
methods
listed
in
Figure
19
20
.
For mixed arrangements with Chinese or Japanese, note the following:
The
display
of
these
controls
needs
to
pay
attention
to
the
direction
of
the
output.
That
is
to
say,
the
primary
display
of
the
number
1,
2,
3,
etc.
is
from
left
to
right.
The
effect
of
the
following
code
is
as
shown
in
Figure
21
22
.
Note
how
the
text
is
centered
on
the
vertical
midline.
The
separator
dots
for
the
numbering
are
not
centre-aligned.
We
should
probably
mention
that.
Also,
shouldn't
the
numbers
be
rotated
counter-clockwise?
In
general,
bookbinding
is
on
the
left
side,
as
shown
in
Figure
22
23
:
The
direction
of
page
turning
is
to
the
left,
as
shown
in
Figure
23
24
:
Generally,
landscape
is
the
default
Mongolian
format,
as
shown
in
Figure
24
25
.
By
default,
pages
should
scroll
from
left
to
right,
as
shown
in
Figure
25
26
.
When the amount of text exceeds the prescribed space available, a scroll bar needs to be displayed. The default display position of the scroll bar is along the bottom of the corresponding space. (The simultaneous display of both horizontal and vertical scroll bars has not been installed).
Columns in Mongolian text should be divided vertically.
The
illustrations
here
include
ordinary
picture
formats,
textboxes,
charts,
media
objects
and
so
on,
all
of
which
are
called
illustrations
in
what
follows.
There
are
many
ways
(as
shown
in
Figure
28
29
)
of
mixing
the
arrangements
of
text
and
illustrations
but,
no
matter
which
way
is
used,
some
principles
need
to
be
obeyed.
When
setting
writing-mode:tb-lr
using
CSS
(grammar
will
have
a
little
difference
according
to
various
browsers),
the
table
will
support
vertical
display
feature
of
Mongolian
script.
When
setting
default
options
for
the
text
in
a
table,
it
will
display
horizontally
centered,
that
is,
the
upper
and
the
lower
center
lines
of
the
table
cell
will
align
at
the
center
line
of
the
baseline
of
the
Mongolian
text,
as
shown
in
Figure
29
30
.
All input controls need to be adjusted to match the characteristics of the vertically typeset Mongolian text. For example, controls like text fields and buttons need to support vertical input and display of text, and furthermore the cursors in text and passwords need to conform to the cursor style as shown in Figure 8 .
The
select
box
appearing
in
the
following
HTML
code
should
be
displayed
as
shown
in
Figure
32
33
.
According
to
the
default
setting,
the
scroll
bar
is
at
the
bottom
and
starts
at
the
left.
To
see
the
contents
at
the
end
of
the
list,
it
scrolls
from
left
to
right.
The
scrolling
of
the
mouse
wheel
should
be
in
accordance
with
illustration
in
Figure
33
34
.
While
selecting
a
column,
the
selected
text
and
the
selected
background
color
should
conform
to
the
principle
of
aligning
to
the
Mongolian
vertically-centered
baseline
(see
the
descriptions
in
Figure
31
32
).
Textarea is an important control, and is required in the text input, edit, and display. Scrollbar movement accords with requirements of the select control in 8.4.1 Select . The display and moving direction of the cursor should be consistent with the standard for cursor movement in 5.1.3 Cursor movement rules . In some browsers, there are functions for stretching the size of the textarea. The stretching icon should be in the lower right corner, and the textarea scaling accords with the mouse dragging. The rows and cols attribute of textarea are the opposite of those in horizontal text. Its specific attributes are as the following: rows {int} : showing the column number and cols {int} : showing the row number.
The
label
control
mainly
considers
text
midcourt
line
aligning
principles.
(
See
the
descriptions
in
7.3
Baselines,
line
height,
etc.
).
The
label
display
for
the
following
code
is
shown
in
Figure
35
36
.
As
shown
in
Figure
36
37
,
which
is
an
example
fieldset
generation
with
the
following
code,
the
components
are
aligned
along
the
centred-vertical
Mongolian
baseline.
Currently, there are some main characters in applied traditional Mongolian script, including basic Mongolian characters, symbols and Mongolian numbers.