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. Three systems are in common use: OpenType, devised by Microsoft and Adobe, Apple's Apple Advanced Typography (AAT), and SIL's Graphite. The lists below provide information about OpenType and AAT features. Graphite does not have a fixed set of features; instead it provides a way for fonts to define their own features.

OpenType typographic features

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 Lua/XeTeX, 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.

The following tables list the features defined in version 1.7 of the OpenType specification. The codes in the "type" column are explained after the tables. OpenType features may be applicable only to certain language scripts or specific languages, or in certain writing modes. The features are split into several tables accordingly.

Features primarily intended for or exclusively required by South-Asian alphasyllabaries (Indic/Brahmic)

Long name	tag	type	Description
Above-base Forms	`abvf`	S1	Replaces the diacritic part of a vowel sign in Khmer etc., e.g. ä to aͤ
Above-base Mark Positioning	`abvm`	P4,5	Positions a diacritic mark on top of the base glyph
Above-base Substitutions	`abvs`	S4	Replaces a pair of base and top diacritic mark by a ligature, e.g. ä to æ
Below-base Forms	`blwf`	S4	Replaces the subscript part of a consonant compound in Khmer etc., e.g. ş to ș
Below-base Mark Positioning	`blwm`	P4,5	Positions a diacritic mark on top of the base glyph
Below-base Substitutions	`blws`	S4	Replaces a pair of base and bottom diacritic mark by a ligature, e.g. ç to cz
Pre-base Forms	`pref`	S4	Khmer 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	Khmer and Gurmukhi, Malayalam
Distance	`dist`	P2	Adjusts horizontal positioning between glyphs
Akhand	`akhn`	S4	Hindi for unbreakable, forms CCV ligatures from two consecutive CV glyphs
Halant Forms	`haln`	S4	Uses halant forms of CV glyphs, indicating that it is read C, may include virama
Half Form	`half`	S4	Uses half-forms of CV glyphs, indicating that it is read as just C
Nukta Forms	`nukt`	S4	Add nukta (dot mark) to glyph, although this is available through Unicode characters
Rakar Forms	`rkrf`	S4	Indic rakar
Reph Form	`rphf`	S4	The reph diacritic changes a CV glyph to its respective rCV glyph
Vattu Variants	`vatu`	S4	Indic vattu
Conjunct Forms	`cjct`	S4
Conjunct Form After Ro	`cfar`	S1	Khmer

Features primarily intended for or exclusively required by East-Asian tetragrams (Chinese, Japanese, Korean, Vietnamese)

Long name	tag	type	Description
Simplified Forms	`smpl`	S1	Replaces sinograms with their simplified versions, may be language dependent
Traditional Forms	`trad`	S1,3	Replaces Chinese characters with their traditional versions
Traditional Name Forms	`tnam`	S1	Japanese alternates for proper names
Expert Forms	`expt`	S1	Typographic alternatives for some Japanese tetragrams
Hojo Kanji Forms	`hojo`		Hojo alternates for Japanese tetragrams
NLC Kanji Forms	`nlck`		NLC alternates for Japanese tetragrams
JIS 78 Forms	`jp78`	S1,3	JIS C 6226-1978 alternates for Japanese tetragrams, not accessible per Unicode
JIS 83 Forms	`jp83`	S1	JIS X 0208-1983 alternates for Japanese tetragrams, not accessible per Unicode
JIS 90 Forms	`jp90`	S1	JIS X 0208-1990 alternates for Japanese tetragrams, not accessible per Unicode
JIS 04 Forms	`jp04`		JIS 2004 alternates for Japanese tetragrams, not accessible per Unicode
Hangul	`hngl`	S1,3	Transliterates Chinese-style characters with Korean Hangul
Leading Jamo Forms	`ljmo`	S4	Initial group of consonants for a synthesized Korean Hangul tetragram
Trailing Jamo Forms	`tjmo`	S4	Final group of consonants for a synthesized Korean Hangul tetragram
Vowel Jamo Forms	`vjmo`	S4	Medial group of vowels for a synthesized Korean Hangul tetragram
Full Widths	`fwid`	S1	Substitutes proportionally spaced character with full-width versions (esp. for Latin letters within Chinese)
Half Widths	`hwid`	S1,P1	Substitutes uniformly-spaced characters with half-width version
Alternate Half Widths	`halt`	P1	Re-positions full-width glyphs on half-width spaces
Third Widths	`twid`	S1,P1	Substitutes uniformly-spaced character with a version of 1/3 width (punctuation, etc.)
Quarter Widths	`qwid`	S1	Replaces uniformly-spaced glyphs with quarter-width ones (punctuation etc.)
Proportional Widths	`pwid`	S1	Replaces uniformly-spaced glyphs with proportional ones
Proportional Alternates	`palt`	P1	Re-positions otherwise monospace characters according to glyph width
Proportional Kana	`pkna`	S1	Kana for use alongside alphabets, without grid typography
Ruby Notation Forms	`ruby`	S1	Ruby characters, small print
Horizontal Kana Alternates	`hkna`	S1	Alternate forms for horizontal kana text, e.g. ー for chōonpu instead of ｜, cf. `vkna`
Vertical Kana	`vkna`	S1	Alternate Japanese kana forms for horizontal text, e.g. ｜ for chōonpu instead of ー, cf. `hkna`
Centered CJK Punctuation	`cpct`	P1	Positions punctuation marks vertically and horizontally

Features primarily intended for or exclusively required by West-Asian (Semitic, Arabic) and other cursive scripts or fonts

Long name	tag	type	Description
Cursive Positioning	`curs`	P3	Precise positioning of a letter's connection to an adjacent one
Justification Alternates	`jalt`	S3	User selectable wider and narrower alternates
Mark Positioning via Substitution	`mset`	S5	Used in Windows 95 for positioning of Arabic marks
Required Ligatures	`rlig`	S3	Ligatures required for correct text display (any script, but in cursive)
Isolated Forms	`isol`	S1	Substitutes a special form of a letter occurring outside a word (required by Arabic and Syriac)
Initial Forms	`init`	S1	Substitutes a special form of a letter occurring at the beginning of a word (required by Arabic and Syriac)
Medial Forms	`medi`	S1	Substitutes a special form of letters between other letters in words (required by Arabic and Syriac)
Medial Form #2	`med2`	S5	Syriac
Terminal Forms	`fina`	S1	Substitutes a special form of a letter at end of words (required by Arabic and Syriac)
Terminal Form #2	`fin2`	S5	Syriac
Terminal Form #3	`fin3`	S5	Syriac
Final Glyph on Line Alternates	`falt`	S3	Replaces final glyph on the line with an alternate.
Stretching Glyph Decomposition	`stch`	S2	Substitutes a special form of a stretchy glyph onto one or more letters (required by Syriac)

Features intended for bicameral [cased] alphabets (Roman, Greek, Cyrillic etc.)

Long name	tag	type	Description
Small Caps	`smcp`	S1	Substitutes lower-case letters with small caps versions
Capitals to Small Caps	`c2sc`	S1	Substitutes capital letters with small caps
Petite Caps	`pcap`	S1	Substitute lower-case letters with their petite caps analogs
Capitals to Petite Caps	`c2pc`	S1	Substitutes capital letters with petite caps
Unicase	`unic`	S1	Replaces lowercase and uppercase letters with a set of single case glyphs
Capital Spacing	`cpsp`	P1	Adjusts spacing between letters in all-capitals text
Case Sensitive Forms	`case`	P1	Replace characters, especially punctuation, with forms better suited for all-capital text, cf. `titl`
Italics	`ital`	S1	Replaces letter with corresponding italic glyph
Ordinals	`ordn`	S6,4	Replaces characters with ordinal forms for use after numbers

Features depending on writing direction

Long name	tag	type	Description
Alternative Vertical Metrics	`valt`	P1	Positions shorter characters to be centered vertically with full-height characters
Alternative Vertical Half Metrics	`vhal`	P1	Positions characters to be centered vertically with half-height characters
Proportional Alternate Vertical Metrics	`vpal`	P1	Re-positions glyphs vertically to be centered on proportional full-height characters
Vertical Alternates	`vert`	S1	A subset of `vrt2`: prefer the latter feature
Vertical Alternates and Rotation	`vrt2`	S1	Replaces characters with forms suitable for vertical writing, possibly by rotating 90°
Vertical Kerning	`vkrn`	P2,8	Fine vertical positioning of characters based on shape
Left-to-right glyph alternates	`ltra`	S1	Replaces characters with forms befitting left-to-right presentation (except mirrored forms)
Left-to-right mirrored forms	`ltrm`	S1	Replaces characters with possibly mirrored forms befitting left-to-right presentation
Right-to-left glyph alternates	`rtla`	S1	Replaces characters with forms befitting right-to-left presentation (except mirrored forms)
Right-to-left mirrored forms	`rtlm`	S1	Replaces characters with possibly mirrored forms befitting right-to-left presentation

Features intended for digits and math

Long name	tag	type	Description
Lining Figures	`lnum`	S1	Replaces numerals with glyphs meant to fit better in all-capitals text, often also `tnum`
Oldstyle Figures	`onum`	S1	Replaces numerals with cased old-style numerals, often also `pnum`
Proportional Figures	`pnum`	S1	Replaces numerals with glyphs of proportional width, often also `onum`
Tabular Figures	`tnum`	S1	Replaces numerals with glyphs of uniform width, often also `lnum`
Fractions	`frac`	S4	Converts figures separated by slash with diagonal fraction
Alternative Fractions	`afrc`	S4	Converts figures separated by slash with alternative stacked fraction form
Denominator	`dnom`	S1	Converts to appropriate fraction denominator form, invoked by `frac`
Numerator	`numr`	S1	Converts to appropriate fraction numerator form, invoked by `frac`
Scientific Inferiors	`sinf`	S1	as in "H₂O", "SO_x" or "YC_bC_r"
Slashed Zero	`zero`	S1	Replaces 0 figure with slashed 0
Mathematical Greek	`mgrk`	S1	Replaces Greek characters with special forms for use in mathematics

Ligation and alternate forms features intended for all scripts

Long name	tag	type	Description
Access All Alternates	`aalt`	S1,3	Special feature: used to present user with choice all alternate forms of the character
Swash	`swsh`	S1,3	Either replaces character with or displays multiple swashed versions
Contextual Swash	`cswh`	S8	Converts letter to a swashed version based on characters around the letter
Contextual Alternates	`calt`	S6	Applies a second substitution feature based on a match of a character pattern within a context of surrounding patterns
Historical Forms	`hist`	S1	Obsolete forms of characters to be applied at the user's discretion, cf. `hlig`
Localized Forms	`locl`	S1	Substitutes character with the preferred form based on script language
Randomize	`rand`	S3	Replaces character with random forms (meant to simulate handwriting)
Alternate Annotation Forms	`nalt`	S1,3	Provides user access to circled digits, inverse letters etc.
Character Variant 1–99	`cv01– cv99`	S3	Multiple variants of a single character, which may not apply to many other characters, see references for voluminous documentation
Stylistic Alternates	`salt`	S1,3	Either replaces with, or displays list of, stylistic alternatives for a character
Stylistic Set 1 – 20	`ss01- ss20`	S1	Replaces character with one from a font-specific set of stylistic alternatives
Subscript	`subs`	S1	Replaces character with subscript version, cf. `numr`
Superscript	`sups`	S1	Replaces character with superscript version, cf. `dnom`
Titling Alternates	`titl`	S1	Replaces characters with forms suited for large type, as in titles
Contextual Ligatures	`clig`	S8	Applies a second ligature feature based on a match of a character pattern within a context of surrounding patterns
Discretionary Ligatures	`dlig`	S4	Ligatures to be applied at the user's discretion
Historical Ligatures	`hlig`	S1	Obsolete ligatures to be applied at the user's discretion
Standard Ligatures	`liga`	S4	Replaces (by default) sequence of characters with a single ligature glyph

Positioning features intended for all scripts

Long name	tag	type	Description
Glyph Composition/Decomposition	`ccmp`	S4,2	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.
Kerning	`kern`	P2,8	Fine horizontal positioning of one glyph to the next, based on the shapes of the glyphs
Mark Positioning	`mark`	P4,5	Fine positioning of a mark glyph to a base character
Mark-to-mark Positioning	`mkmk`	P6	Fine positioning of a mark glyph to another mark character
Optical Bounds	`opbd`	P1	Re-positions glyphs at beginning and end of line, for precise justification of text.
Left Bounds	`lfbd`	P1	Re-positions glyphs at end of line. Called by `opbd`.
Right Bounds	`rtbd`	P1	Re-positions glyphs at beginning of line. Called by `opbd`.

Special features intended for all scripts

Long name	tag	type	Description
Optical size	`size`		Not a lookup: feature's table provides to applications information about the appearance and intent of the font, to aid in font selection.
Ornaments	`ornm`	S3,1	Decorative alternates for the bullet character •

Legend of substitution and positioning codes

Below are listed the OpenType lookup table types, as used in the "type" column in the above tables. S stands for substitution, and P stands for positioning. 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

"Layout tag registry", OpenType spec, Microsoft
"Font Feature Registry", Fonts, Apple – AAT layout tag specs
OpenType User Guide for Adobe Fonts (PDF), Adobe
OpenType user guide (PDF), Fontfont
An Introduction to OpenType Substitution Features, I love typography

Typography terminology

Page

Paragraph

Character

Typeface anatomy	Counter Diacritics Dingbat Glyph Initial Kerning Letter-spacing Ligature Subscript and superscript Swash Text figures Tittle

Capitalization	All caps CamelCase Letter case Petite caps Small caps

Visual distinction	Italics Oblique Bold Color Underline 𝔹𝕝𝕒𝕔𝕜𝕓𝕠𝕒𝕣𝕕 𝕓𝕠𝕝𝕕 𝕭𝖑𝖆𝖈𝖐𝖑𝖊𝖙𝖙𝖊𝖗 Infant

Vertical aspects	Ascender Baseline Cap height Descender Median Overshoot x-height

Classifications

Roman type	Antiqua (Old Style) Didone (Modern) Sans-serif Script Serif Slab serif Transitional Reverse-contrast

Blackletter type	Fraktur Rotunda Schwabacher Textualis

Gaelic type	Insular Uncial

Specialist	Record type

Category
Commons
Portal

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