List of typographic features

State-of-the-art digital typographic systems have solved virtually all the demands of traditional typography and have expanded the possibilities with many new features. The two lists below provide information about many features

Digital Typographic Systems

OpenType, a font format devised by Microsoft and Adobe Systems, is one modern implementation of typographic features in typefaces, and Apple Inc's Apple Advanced Typography (AAT) is another. The OpenType format defines a number of typographic features that a particular font may support; some software, such as Adobe InDesign or recent versions of TeX, gives users control of these, for example to enable fancy stylistic capital letters (swash caps) or to choose between ranging (full-height) and non-ranging (old-style, or lower-case) digits.

OpenType Typographic Features

Long name	tag	type	script	Description
Above-base Forms	abvf	S1	Indic
Above-base Mark Positioning	abvm	P4,5	Indic
Above-base Substitutions	abvs	S4	Indic
Access All Alternates	aalt	S1,3	any	Used to present user with choice all alternate forms of the character
Akhand	akhn	S4	Indic
Alternate Annotation	nalt	S1,3	any
Alternate Half Widths	halt	P1	CJKV	Re-positions full-width glyphs on half-width spaces
Alternative Fractions	afrc	S4	any	Converts figures separated by slash with alternative nut fraction form
Alternative Vertical Metrics	valt	P1	vert.	Positions shorter characters to be centered vertically with full-height characters
Alternative Vertical Half Metrics	vhal	P1	vert.	Positions characters to be centered vertically with half-height characters
Below-base Forms	blwf	S4	Indic
Below-base Mark Positioning	blwm	P4,5	Indic
Below-base Substitutions	blws	S4	Indic
Capital Spacing	cpsp	P1	cased	Adjusts spacing between letters in all-capitals text
Capitals to Petite Caps	c2pc	S1	cased	Substitutes capital letters with petite caps
Capitals to Small Caps	c2sc	S1	cased	Substitutes capital letters with small caps
Case Sensive Forms	case	P1	cased	Replace characters, especially punctuation, with forms better suited for all-capital text
Centered CJK Punctuation	cpct	P1	CJKV	Positions punctuation marks vertically and horizontally
Character Variant 01 - 99	cv01- cv99	S3	any	Multiple variants of a single character, which may not apply to many other characters. See references for voluminous documentation.
Conjunct Forms	cjct	S4	Indic
Conjunct Form After Ro	cfar	S1	Khm.
Contextual Alternates	calt	S6	any	Applies a second substitution feature based on a match of a character pattern within a context of surrounding patterns
Contextual Ligatures	clig	S8	any	Applies a second ligature feature based on a match of a character pattern within a context of surrounding patterns
Contextual Swash	cswh	S8	any	Converts letter to a swashed version based on characters around the letter
Cursive Positioning	curs	P3	curs.	Precise positioning of a letter's connection to an adjacent one
Denominator	dnom	S1	any	Converts to appropriate fraction denominator form. Invoked by frac.
Discretionary Ligatures	dlig	S4	any	Ligatures to be applied at the user's discretion
Distance	dist	P2	Indic	Adjusts horizontal positioning between glyphs
Expert Forms	expt	S1	Jap.
Final Glyph on Line Alternates	falt	S3	curs.	Replaces final glyph on the line with an alternate.
Fractions	frac	S4	any	Converts figures separated by slash with diagonal fraction
Terminal Form #2	fin2	S5	Syr.
Terminal Form #3	fin3	S5	Syr.
Full Widths	fwid	S1	CJKV	Substitutes proportionally spaced character with full-width versions (esp. for Latin letters within Chinese)
Glyph Composition/Decomposition	ccmp	S4,2	any	Either calls a ligature replacement on a sequence of characters or replaces a character with a sequence of glyphs. Provides logic that can for example effectively alter the order of input characters.
Halant Forms	haln	S4	Indic
Half Form	half	S4	Indic
Half Widths	hwid	S1,P1	CJKV	Substitutes uniformly-spaced characters with a version of 1/2 width
Hangul	hngl	S1,3	Kor.	Replaces Chinese-style characters with Korean Hangul
Historical Forms	hist	S1	any	Obsolete forms of characters to be applied at the user's discretion
Historical Ligatures	hlig	S1	any	Obsolete ligatures to be applied at the user's discretion
Horizontal Kana Alternates	hkna	S1	Kana
Hojo Kanji Forms	hojo		Kanji
Initial Forms	init	S1	any	Substitutes a special form of a letter occurring at the beginning of a word (required by Arabic and Syriac)
Isolated Forms	isol	S1	curs.	Substitutes a special form of a letter occurring outside a word (required by Arabic and Syriac)
Italics	ital	S1	Lat.	Replaces letter with corresponding italic glyph
JIS 04 Forms	jp04		Jap.
JIS 78 Forms	jp78	S1,3	Jap.
JIS 83 Forms	jp83	S1	Jap.
JIS 90 Forms	jp90	S1	Jap.
Justification Alternates	jalt	S3	curs.
Kerning	kern	P2,8	any	Fine horizontal positioning of one glyph to the next, based on the shapes of the glyphs
Lining Figures	lnum	S1	cased	Replaces numerals with glyphs meant to fit better in all-capitals text
Leading Jamo Forms	ljmo	S4	Kor.
Left Bounds	lfbd	P1	any	Re-positions glyphs at end of line. Called by opbd.
Left-to-right glyph alternates	ltra	S1	ltr	Replaces characters with possibly mirrored forms befitting left-to-right presentation
Left-to-right mirrored forms	ltrm	S1	ltr	Replaces characters with forms befitting left-to-right presentation (except mirrored forms)
Localized Forms	locl	S1	any	Substitutes character with the preferred form based on script language
Mark Positioning	mark	P4,5	any	Fine positioning of a mark glyph to a base character
Mark-to-mark Positioning	mkmk	P6	any	Fine positioning of a mark glyph to another mark character
Mathematical Greek	mgrk	S1	any	Replaces Greek characters with special forms for use in mathematics.
Medial Forms	medi	S1	any	Substitutes a special form of letters between other letters in words (required by Arabic and Syriac)
Medial Form #2	med2	S5	Syr.
mset	mset	S5	curs.	Deprecated. Used in Windows 95 for positioning of Arabic marks.
NLC Kanji Forms	nlck		Kanji
Nukta Forms	nukt	S4	Indic
Numerator	numr	S1	any	Converts to appropriate fraction numerator form. Invoked by frac.
Oldstyle Figures	onum	S1	any	Replaces numerals with old-style numerals
Optical Bounds	opbd	P1	any	Re-positions glyphs at beginning and end of line, for precise justification of text.
Ordinals	ordn	S6,4	Lat.	Replaces characters with ordinal forms for use after numbers
Ornaments	ornm	S3,1	any
Petite Caps	pcap	S1	cased	Substitute lower-case letters with their petite caps analogs
Pre-base Forms	pref	S4	Khm.	(and other similar scripts: Myanmar, Malayalam, Telugu)
Pre-base Substitutions	pres	S4,5	Indic
Post-base Substitutions	psts	S4	Indic	(any alphabetic?)
Post-base Forms	pstf	S4	Khm.	(and Gurmukhi, Malayalam)
Proportional Alternates	palt	P1	CJKV	Re-positions otherwise monospace characters according to glyph width
Proportional Alternate Vertical Metrics	vpal	P1	vert.	Re-positions glyphs vertically to be centered on proportional full-height characters
Proportional Figures	pnum	S1	any	Replaces numerals with glyphs of proportional width
Proportional Kana	pkna	S1	Kana
Proportional Widths	pwid	S1	CJKV	Replaces uniformly-spaced glyphs with proportional ones
Quarter Widths	qwid	S1	CJKV	Replaces uniformly-spaced glyphs with quarter-width ones (punctuation etc.)
Randomize	rand	S3	any	Replaces chararacter with random forms (meant to simulate handwriting)
Rakar Forms	rkrf	S4	Indic
Reph Form	rphf	S4	Indic
Required Ligatures	rlig	S3	curs.	Ligatures required for correct text display (esp. in Arabic and Syriac)
Right Bounds	rtbd	P1	any	Re-positions glyphs at beginning of line. Called by opbd.
Right-to-left glyph alternates	rtla	S1	rtl	Replace characters with forms befitting right-to-left presentation (except mirrored forms)
Right-to-left mirrored forms	rtlm	S1	rtl	Replace characters with possibly mirrored forms befitting right-to-left presentation
Ruby Notation Forms	ruby	S1	CJKV
Scientific Inferiors	sinf	S1	any
Simplified Forms	smpl	S1	CJKV	Replaces Chinese characters with their simplified versions
Optical size	size		any	Not a lookup: feature's table provides to applications information about the appearance and intent of the font, to aid in font selection.
Slashed Zero	zero	S1	any	Replaces 0 figure with slashed 0
Small Caps	smcp	S1	cased	Substitutes lower-case letters with small caps versions
Standard Ligatures	liga	S4	any	Replaces (by default) sequence of characters with a single ligature glyph
Stylistic Alternates	salt	S1,3	any	Replaces character with stylistic alternative
Stylistic Sets	ss01- ss20	S1	any	Replaces character with a one from a font-specific set of stylistic alternatives
Subscript	subs	S1	any	Replaces character with subscript version
Superscript	sups	S1	any	Replaces character with superscript version
Swash	swsh	S1,3	any	Replaces character with swashed version
Tabular Figures	tnum	S1	any	Replaces numerals with glyphs of uniform width
Terminal Forms	fina	S1	any	Substitutes a special form of a letter at end of words (required by Arabic and Syriac)
Third Widths	twid	S1,P1	CJKV	Substitutes uniformly-spaced character with a version of 1/3 width (punctuation, etc.)
Titling Alternates	titl	S1	any	Replaces characters with forms suited for large type, as in titles
Traditional Forms	trad	S1,3	CJKV	Replaces Chinese characters with their traditional versions
Traditional Name Forms	tnam	S1	Jap.
Trailing Jamo Forms	tjmo	S4	Kor.
Unicase	unic	S1	cased	Replaces lowercase and uppercase letters with a set of single case glyphs
Vattu Variants	vatu	S4	Indic
Vertical Alternates	vert	S1	vert.	A subset of vrt2: prefer the latter feature.
Vertical Alternates and Rotation	vrt2	S1	vert.	Replaces characters with forms suitable for vertical writing, possibly by rotating 90°
Vertical Kana	vkna	S1	Kana
Vertical Kerning	vkrn	P2,8	vert.	Fine vertical positioning of characters based on shape
Vowel Jamo Forms	vjmo	S4	Kor.

OpenType features may be applicable only to certain language scripts or specific languages, or in certain writing modes. The script column above indicates such dependencies.

abbrev.	applicable in
any	any script
cased	bicameral scripts (those with a case distinction) such as Greek, Latin, and Cyrillic
curs.	cursive mode; required in Arabic and Syriac
vert.	vertical mode; especially used in CKJV
ltr	left-to-right mode
rtl	right-to-left mode
mono	monospaced mode
CJKV	Chinese, Japenese, Korean, Vietnamese -- especially in display of block ideographic characters
Indic	Indic scripts
Jap.	Japanese only
Kanji	Japanese Kanji only
Kana	Kana only (Japanese, Ainu)
Kor.	Korean only
Lat.	Latin-based scripts only
Khm.	Khmer script, and often other similar, Brahmi-based ones
Syr.	Syriac only

OpenType lookup table types, used in the "type" column in the above table. Note that often a feature can be implemented by more than one type of table, and that sometimes the specification fails to explicitly indicate the table type.

abbrev.	type	description
S1	GSUB 1	simple substitution of one glyph with another
S2	GSUB 2	multiple substitution of one character by several glyphs
S3	GSUB 3	variant selection
S4	GSUB 4	ligatures
S5	GSUB 5	contextual substitution
S6	GSUB 6	chained contextual substitution
S7	GSUB 7	extension for GSUB tables past 64kB
S8	GSUB 8	reverse chained contextual substitution
P1	GPOS 1	positioning of single glyph
P2	GPOS 2	positioning of pair of glyphs
P3	GPOS 3	cursive attachment
P4	GPOS 4	positioning of mark glyphs relative to base
P5	GPOS 5	positioning of mark glyphs relative to ligature
P6	GPOS 6	positioning of mark glyphs relative to another mark glyph
P7	GPOS 7	contextual positioning
P8	GPOS 8	extended contextual positioning
P9	GPOS 9	extension for GPOS tables past 64kB

AAT Typographic Features

Features that take one value, mutual exclusive from the rest:

• Annotation nalt
  • No Annotation
  • Box Annotation
  • Rounded Box Annotation
  • Circle Annotation
  • Inverted Circle Annotation
  • Parenthesis Annotation
  • Period Annotation
  • Roman Numeral Annotation
  • Diamond Annotation
• Character Alternatives
  • No Alternates
  • … rand; aalt, calt, falt, jalt, salt, ssXX, hkna/vkna, rtla, vrt2
• Character Shape half, ruby; ljmo, vjmo, tjmo
  • Traditional Characters trad
  • Simplified Characters smpl
  • JIS 1978 Characters jp78
  • JIS 1983 Characters jp83
  • JIS 1990 Characters jp90
  • Traditional Characters, Alternative Set 1…5 tnam, hojo, nlck
  • Expert Characters expt, locl
• CJK Roman Spacing
  • Half-width hwid, halt
  • Proportional pwid, palt
  • Default Roman
  • Full-width Roman fwid
• Cursive Connection init, medi/med2, fina/fin2/fin3; haln, nukt, vatu, rphf, pres, pstf/psts
  • Unconnected isol
  • Partially Connected calt, clig
  • Cursive curs
• Design Complexity
  • Design Level 1
  • Design Level …
• Diacritics
  • Show Diacritics
  • Hide Diacritics
  • Decompose Diacritics ccmp
• Fractions
  • No Fractions
  • Vertical Fractions afrc
  • Diagonal Fractions frac, dnom, numr
• Ideographic Spacing
  • Full Width fwid
  • Proportional pwid, palt
• Kana Spacing
  • Full Width fwid
  • Proportional pwid, palt
• Letter Case case
  • Upper & Lower Case
  • All Caps
  • All Lower Case
  • Small Caps smcp, pcap
  • Initial Caps c2sc, c2pc
  • Initial Caps and Small Caps
• Number Case
  • Lower Case Numbers onum
  • Upper Case Numbers lnum
• Number Spacing
  • Monospaced Numbers tnum
  • Proportional Numbers pnum
• Ornament Sets ornm
  • None
  • Dingbats
  • Pi Characters
  • Fleurons
  • Decorative Borders
  • International Symbols
  • Math Symbols mgrk
• Text Spacing
  • Proportional pwid, palt
  • Monospace fwid
  • Half-width hwid, halt
  • Normal
• Vertical Position
  • No Vertical Position
  • Superiors supr
  • Inferiors subs, sinf
  • Ordinals ordn

Features that take a number of values:

• Ligatures
  • Required Ligatures rlig, clig
  • Common Ligatures liga
  • Rare Ligatures hlig, dlig
  • Logos
  • Rebus Pictures
  • Diphthong Ligatures
  • Squared Ligatures
  • Squared Ligatures, Abbreviated
• Mathematical Extras
  • Hyphen to Minus (‘-’ → ‘−’)
  • Asterisk to Multiply (‘*’ → ‘×’)
  • Slash to Divide (‘/’ → ‘÷’)
  • Inequality Ligatures
  • Exponents
• Smart Swashes swsh, cswh
  • Word Initial Swashes
  • Word Final Swashes
  • Line Initial Swashes
  • Line Final Swashes falt
  • Non-Final Swashes jalt
• Style Options
  • No Style Options
  • Display Text size
  • Engraved Text
  • Illuminated Caps
  • Titling Caps titl
  • Tall Caps
• Transliteration locl
  • No Transliteration
  • Hanja to Hangul
  • Hanja to Hangul, Alternative Set 1…3
  • Hiragana to Katakana
  • Katakana to Hiragana
  • Kana to Romanization
  • Romanization to Hiragana
  • Romanization to Katakana
• Typographic Extras
  • Hyphens to Em Dash (‘--’ → ‘—’)
  • Hyphen to En Dash (‘-’ → ‘–’)
  • Unslashed Zero zero
  • Form Interrobang (‘!?’/‘?!’ → ‘‽’)
  • Smart Quotes (‘"'"’ → ‘“’”’)
  • Periods to Ellipsis (‘...’ → ‘…’)

Binary features that can only be turned on:

• All Typographic Features
• Linguistic Rearrangement
• Overlapping Characters
• Vertical Substitution

External links

• Adobe Feature Tag Registry - OpenType layout tag specs
• Microsoft OpenType Layout tag registry
• Apple Font Feature Registry - AAT layout tag specs
• OpenType User Guide for Adobe Fonts
• Fontfont OpenType user guide