OpenType feature tag list

This is a comprehensive list of Open Type feature tags. For further details see the main Open Type article.

List of standard feature tags

*'aalt' Access All Alternates
*'abvf' Above-base Forms
*'abvm' Above-base Mark Positioning
*'abvs' Above-base Substitutions
*'afrc' Alternative Fractions
*'akhn' Akhands
*'blwf' Below-base Forms
*'blwm' Below-base Mark Positioning
*'blws' Below-base Substitutions
*'calt' Contextual Alternates
*'case' Case-Sensitive Forms
*'ccmp' Glyph Composition / Decomposition
*'clig' Contextual Ligatures
*'cpsp' Capital Spacing
*'cswh' Contextual Swash
*'curs' Cursive Positioning
*'c2sc' Small Capitals From Capitals
*'c2pc' Petite Capitals From Capitals
*'dist' Distances
*'dlig' Discretionary Ligatures
*'dnom' Denominators
*'expt' Expert Forms
*'falt' Final Glyph on Line Alternates
*'fin2' Terminal Forms #2
*'fin3' Terminal Forms #3
*'fina' Terminal Forms
*'frac' Fractions
*'fwid' Full Widths
*'half' Half Forms
*'haln' Halant Forms
*'halt' Alternate Half Widths
*'hist' Historical Forms
*'hkna' Horizontal Kana Alternates
*'hlig' Historical Ligatures
*'hngl' Hangul
*'hojo' Hojo Kanji Forms
*'hwid' Half Widths
*'init' Initial Forms
*'isol' Isolated Forms
*'ital' Italics
*'jalt' Justification Alternates
*'jp04' JIS2004 Forms
*'jp78' JIS78 Forms
*'jp83' JIS83 Forms
*'jp90' JIS90 Forms
*'kern' Kerning
*'lfbd' Left Bounds
*'liga' Standard Ligatures
*'ljmo' Leading Jamo Forms
*'lnum' Lining Figures
*'locl' Localized Forms
*'mark' Mark Positioning
*'med2' Medial Forms #2
*'medi' Medial Forms
*'mgrk' Mathematical Greek
*'mkmk' Mark to Mark Positioning
*'mset' Mark Positioning via Substitution
*'nalt' Alternate Annotation Forms
*'nlck' NLC Kanji Forms
*'nukt' Nukta Forms
*'numr' Numerators
*'onum' Oldstyle Figures
*'opbd' Optical Bounds
*'ordn' Ordinals
*'ornm' Ornaments
*'palt' Proportional Alternate Widths
*'pcap' Petite Capitals
*'pnum' Proportional Figures
*'pres' Pre-Base Substitutions
*'pstf' Post-base Forms
*'psts' Post-base Substitutions
*'pwid' Proportional Widths
*'qwid' Quarter Widths
*'rand' Randomize
*'rlig' Required Ligatures
*'rphf' Reph Forms
*'rtbd' Right Bounds
*'rtla' Right-to-left Alternates
*'ruby' Ruby Notation Forms
*'salt' Stylistic Alternates
*'sinf' Scientific Inferiors
*'size' Optical size
*'smcp' Small Capitals
*'smpl' Simplified Forms
*'ss01' to 'ss20' Stylistic Set 1 to 20
*'subs' Subscript
*'sups' Superscript
*'swsh' Swash
*'titl' Titling
*'tjmo' Trailing Jamo Forms
*'tnam' Traditional Name Forms
*'tnum' Tabular Figures
*'trad' Traditional Forms
*'twid' Third Widths
*'unic' Unicase
*'valt' Alternate Vertical Metrics
*'vatu' Vattu Variants
*'vert' Vertical Writing
*'vhal' Alternate Vertical Half Metrics
*'vjmo' Vowel Jamo Forms
*'vkna' Vertical Kana Alternates
*'vkrn' Vertical Kerning
*'vpal' Proportional Alternate Vertical Metrics
*'vrt2' Vertical Alternates and Rotation
*'zero' Slashed Zero

Features supported by Mac OS X

:"See also Datafork TrueType."

As of Mac OS X v10.5.4 (Leopard), Apple has started including support for OpenType features in the operating system itself since Tiger, relieving application developers of the task. However there are few caveats:
* If a font is detected to have OpenType tables, any AAT layout tables present are ignored except the 'kern' table if there is no 'kern' or 'vkrn' features within the font's GPOS table. Mac OS X CoreText technology provides thorough OpenType Arabic shaping as of Mac OS X v10.5 (but is currently missing other complex scripts such as Indic shaping). Whereas Carbon ATSUI technology uses only the Latin OpenType shaping features and consequently does not shape any of the complex scripts using OpenType data though performs thorough complex script layout utilizing font's with AAT shaping tables, as does CoreText.
* Only the following GDEF/GPOS/GSUB features (tags) are confirmed as supported:
** case: Case-sensitive forms
** ccmp: Glyph composition/decomposition
** clig: Contextual ligatures
** cpsp: Capital spacing
** curs: Cursive positioning
** c2pc: Petite capitals from Capitals
** c2sc: Small capitals from Capitals
** dlig: Discretionary ligatures
** expt: Expert CJK forms
** fina: Terminal forms
** frac: Fractions
** fwid: Full widths
** halt: Alternate half widths
** hist: Historical forms
** hkna: Horizontal Kana alternates
** hlig: Historical ligatures
** hngl: Hangul
** hojo: Hojo Kanji forms
** hwid: Half widths
** init: Initial forms
** isol: Isolated forms
** ital: Italics
** jp78: JIS78 forms
** jp83: JIS83 forms
** jp90: JIS90 forms
** jp04: JIS2004 forms
** kern: Kerning
** liga: Common ligatures
** lnum: Lining figures
** mark: Mark-to-base positioning
** medi: Medial forms
** mgrk: Mathematical Greek
** mkmk: Mark-to-mark positioning
** mset: Mark positioning via substitution
** nlck: NLC Kanji forms
** numr: Numerators
** onum: Oldstyle numerals
** opbd: Optical bounds
** ordn: Ordinals
** palt: Proportional alternate widths
** pcap: Petite capitals
** pnum: Proportional numerals
** pwid: Proportional figures
** qwid: Quarter widths
** rlig: Required ligatures
** ruby: Ruby notation forms
** sinf: Scientific inferiors
** smcp: Small capitals
** smpl: Simplified forms
** ss01 to ss20: Stylistic sets (but only supported as mutually exclusive - this will be changed for SnowLeopard)
** subs: Subscript
** sups: Superscript
** titl: Titling
** tnum: Tabular figures
** trad: Traditional forms
** twid: Third widths
** unic: Unicase forms
** valt: Alternate vertical metrics
** vert: Vertical alternates
** vhal: Alternate vertical half metrics
** vjmo: Vowel Jamo forms
** vkna: Vertical Kana alternates
** vkrn: Vertical kerning
** vpal: Proportional alternate vertical metrics
** vrt2: Vertical alternates and rotation
** zero: Slashed zero
** "this list is incomplete"
* These features are known not to be supported:
** abvm: Above-base mark positioning
** abvs: Above-base substitution
** akhn: Akhand ligature
** blwf: Below-base form
** blwm: Below-base mark positioning
** blws: Below-base substitution
** calt: Connecting/contextual alternates
** dist: Distances
** half: Half-form (pre-base form)
** haln: Halant form substitution
** nukt: Nukta form
** rphf: Reph form
** pres: Pre-base substitution
** pstf: Post-base form
** psts: Post-base substitution
** vatu: Vattu variants

Notes

=References=