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documents, the logical constructs known as character data and attribute values consist of sequences of , in which each character can manifest directly (representing itself), or can be represented by a series of characters called a character reference, of which there are two types: a
and a character entity reference. This article lists the character entity references that are valid in HTML and XML documents.
A character entity reference refers to the content of a named entity. An entity declaration is created by using the &!ENTITY name "value"& syntax in a
A numeric character reference refers to a character by its / code point, and uses the format
where nnnn is the code point in
form, and hhhh is the code point in
form. The x must be lowercase in XML documents. The nnnn or hhhh may be any number of digits and may include leading zeros. The hhhh may mix uppercase and lowercase, though uppercase is the usual style.
In contrast, a character entity reference refers to a character by the name of an
which has the desired character as its replacement text. The entity must either be predefined (built into the markup language) or explicitly declared in a
(DTD). The format is the same as for any entity reference:
where name is the case-sensitive name of the entity. The semicolon is required.
ISO Entity Sets:
supplied a comprehensive set of entity declarations for characters widely used in Western technical and reference publishing, for Latin, Greek and Cyrillic scripts. The
also contributed entities for mathematical characters.
HTML Entity Sets: Early versions of
built in small subsets of these, relating to characters found in three Western 8-bit fonts.
MathML Entity Sets: The
developed a set of entity declarations for
characters.
XML Entity Sets: The
MathML Working Group took over maintenance of the ISO public entity sets, combined with the MathML and documents them in . This set can support the requirements of ,
and as an input to future versions of HTML.
adopts the XML entities as , however it restates them without reference to their sources and does not group them into sets. The HTML 5 specification additionally provides mappings from the names to Unicode character sequences using .
Numerous other entity sets have been developed for special requirements, and for major and minority scripts. However, the advent of
has largely superseded them.
The XML specification does not use the term "character entity" or "character entity reference". The XML specification defines five "predefined entities" representing special characters, and requires that all XML processors honor them. The entities can be explicitly declared in a DTD, as well, but if this is done, the replacement text must be the same as the built-in definitions. XML also allows other named entities of any size to be defined on a per-document basis.
The table below lists the five XML predefined entities. The "Name" column mentions the entity's name. The "Character" column shows the character. To render the character, the format & for example, & renders as &. The "Unicode code point" column cites the character via standard UCS/Unicode "U+" notation, which shows the character's code point in hexadecimal. The decimal equivalent of the code point is then shown in parentheses. The "Standard" column indicates the first version of XML that includes the entity. The "Description" column cites the character via its canonical UCS/Unicode name, in English.
Unicode code point (decimal)
Description
U+0022 (34)
U+0026 (38)
U+0027 (39)
(apostrophe-quote)
U+003C (60)
U+003E (62)
The HTML 4 DTDs define 252 named entities, references to which act as mnemonic aliases for certain Unicode characters. The HTML 4 specification requires the use of the standard DTDs and does not allow users to define additional entities.
In the table below, the "Standard" column indicates the first version of the HTML DTD that defines the character entity reference. HTML 4.01 does not provide any new character references.
To use one of these character entity references in an HTML or XML document, enter an ampersand followed by the entity name and a semicolon, e.g., &
Unicode code point (decimal)
Old ISO subset
Description
U+0022 (34)
HTMLspecial
(APL quote)
U+0026 (38)
HTMLspecial
U+0027 (39)
HTMLspecial
(apostrophe-quote); see
U+003C (60)
HTMLspecial
U+003E (62)
HTMLspecial
U+00A0 (160)
no-break space ()
U+00A1 (161)
U+00A2 (162)
U+00A3 (163)
U+00A4 (164)
U+00A5 (165)
U+00A6 (166)
broken bar (broken vertical bar)
U+00A7 (167)
U+00A8 (168)
(spacing diaeresis); see
U+00A9 (169)
U+00AA (170)
U+00AB (171)
left-pointing double angle quotation mark (left pointing )
U+00AC (172)
U+00AD (173)
(discretionary hyphen)
U+00AE (174)
registered sign ()
U+00AF (175)
(spacing macron, overline, APL overbar)
U+00B0 (176)
U+00B1 (177)
(plus-or-minus sign)
U+00B2 (178)
superscript two (superscript digit two, squared)
U+00B3 (179)
superscript three (superscript digit three, cubed)
U+00B4 (180)
(spacing acute)
U+00B5 (181)
micro sign
U+00B6 (182)
sign (paragraph sign)
U+00B7 (183)
(Georgian comma, Greek middle dot)
U+00B8 (184)
(spacing cedilla)
U+00B9 (185)
superscript one (superscript digit one)
U+00BA (186)
U+00BB (187)
right-pointing double angle quotation mark (right pointing guillemet)
U+00BC (188)
vulgar fraction one quarter (fraction one quarter)
U+00BD (189)
vulgar fraction one half (fraction one half)
U+00BE (190)
vulgar fraction three quarters (fraction three quarters)
U+00BF (191)
(turned question mark)
U+00C0 (192)
Latin capital letter A with
(Latin capital letter A grave)
U+00C1 (193)
Latin capital letter A with
U+00C2 (194)
Latin capital letter A with
U+00C3 (195)
Latin capital letter A with
U+00C4 (196)
Latin capital letter A with
U+00C5 (197)
Latin capital letter A with ring above (Latin capital letter A ring)
U+00C6 (198)
Latin capital letter AE (Latin capital ligature AE)
U+00C7 (199)
Latin capital letter C with
U+00C8 (200)
Latin capital letter E with
U+00C9 (201)
Latin capital letter E with
U+00CA (202)
Latin capital letter E with
U+00CB (203)
Latin capital letter E with
U+00CC (204)
Latin capital letter I with
U+00CD (205)
Latin capital letter I with
U+00CE (206)
Latin capital letter I with
U+00CF (207)
Latin capital letter I with
U+00D0 (208)
Latin capital letter
U+00D1 (209)
Latin capital letter N with
U+00D2 (210)
Latin capital letter O with
U+00D3 (211)
Latin capital letter O with
U+00D4 (212)
Latin capital letter O with
U+00D5 (213)
Latin capital letter O with
U+00D6 (214)
Latin capital letter O with
U+00D7 (215)
U+00D8 (216)
Latin capital letter O with stroke (Latin capital letter O slash)
U+00D9 (217)
Latin capital letter U with
U+00DA (218)
Latin capital letter U with
U+00DB (219)
Latin capital letter U with
U+00DC (220)
Latin capital letter U with
U+00DD (221)
Latin capital letter Y with
U+00DE (222)
Latin capital letter
U+00DF (223)
Latin small letter sharp s (ess-zed); see German
U+00E0 (224)
Latin small letter a with
U+00E1 (225)
Latin small letter a with
U+00E2 (226)
Latin small letter a with
U+00E3 (227)
Latin small letter a with
U+00E4 (228)
Latin small letter a with
U+00E5 (229)
Latin small letter a with ring above
U+00E6 (230)
Latin small letter ae (Latin small ligature ae)
U+00E7 (231)
Latin small letter c with
U+00E8 (232)
Latin small letter e with
U+00E9 (233)
Latin small letter e with
U+00EA (234)
Latin small letter e with
U+00EB (235)
Latin small letter e with
U+00EC (236)
Latin small letter i with
U+00ED (237)
Latin small letter i with
U+00EE (238)
Latin small letter i with
U+00EF (239)
Latin small letter i with
U+00F0 (240)
Latin small letter
U+00F1 (241)
Latin small letter n with
U+00F2 (242)
Latin small letter o with
U+00F3 (243)
Latin small letter o with
U+00F4 (244)
Latin small letter o with
U+00F5 (245)
Latin small letter o with
U+00F6 (246)
Latin small letter o with
U+00F7 (247)
division sign ()
U+00F8 (248)
Latin small letter o with stroke (Latin small letter o slash)
U+00F9 (249)
Latin small letter u with
U+00FA (250)
Latin small letter u with
U+00FB (251)
Latin small letter u with
U+00FC (252)
Latin small letter u with
U+00FD (253)
Latin small letter y with
U+00FE (254)
Latin small letter
U+00FF (255)
Latin small letter y with
HTMLspecial
Latin capital ligature oe
HTMLspecial
Latin small ligature oe
HTMLspecial
Latin capital letter s with
HTMLspecial
Latin small letter s with
HTMLspecial
Latin capital letter y with
HTMLsymbol
Latin small letter f with hook (, florin)
U+02C6 (710)
HTMLspecial
modifier letter
U+02DC (732)
HTMLspecial
HTMLsymbol
Greek capital letter Alpha
HTMLsymbol
Greek capital letter Beta
HTMLsymbol
Greek capital letter Gamma
HTMLsymbol
Greek capital letter Delta
HTMLsymbol
Greek capital letter Epsilon
HTMLsymbol
Greek capital letter Zeta
HTMLsymbol
Greek capital letter Eta
HTMLsymbol
Greek capital letter Theta
HTMLsymbol
Greek capital letter Iota
U+039A (922)
HTMLsymbol
Greek capital letter Kappa
U+039B (923)
HTMLsymbol
Greek capital letter Lambda
U+039C (924)
HTMLsymbol
Greek capital letter Mu
U+039D (925)
HTMLsymbol
Greek capital letter Nu
U+039E (926)
HTMLsymbol
Greek capital letter Xi
U+039F (927)
HTMLsymbol
Greek capital letter Omicron
U+03A0 (928)
HTMLsymbol
Greek capital letter Pi
U+03A1 (929)
HTMLsymbol
Greek capital letter Rho
U+03A3 (931)
HTMLsymbol
Greek capital letter Sigma
U+03A4 (932)
HTMLsymbol
Greek capital letter Tau
U+03A5 (933)
HTMLsymbol
Greek capital letter Upsilon
U+03A6 (934)
HTMLsymbol
Greek capital letter Phi
U+03A7 (935)
HTMLsymbol
Greek capital letter Chi
U+03A8 (936)
HTMLsymbol
Greek capital letter Psi
U+03A9 (937)
HTMLsymbol
Greek capital letter Omega
U+03B1 (945)
HTMLsymbol
Greek small letter alpha
U+03B2 (946)
HTMLsymbol
Greek small letter beta
U+03B3 (947)
HTMLsymbol
Greek small letter gamma
U+03B4 (948)
HTMLsymbol
Greek small letter delta
U+03B5 (949)
HTMLsymbol
Greek small letter epsilon
U+03B6 (950)
HTMLsymbol
Greek small letter zeta
U+03B7 (951)
HTMLsymbol
Greek small letter eta
U+03B8 (952)
HTMLsymbol
Greek small letter theta
U+03B9 (953)
HTMLsymbol
Greek small letter iota
U+03BA (954)
HTMLsymbol
Greek small letter kappa
U+03BB (955)
HTMLsymbol
Greek small letter lambda
U+03BC (956)
HTMLsymbol
Greek small letter mu
U+03BD (957)
HTMLsymbol
Greek small letter nu
U+03BE (958)
HTMLsymbol
Greek small letter xi
U+03BF (959)
HTMLsymbol
Greek small letter omicron
U+03C0 (960)
HTMLsymbol
Greek small letter pi
U+03C1 (961)
HTMLsymbol
Greek small letter rho
U+03C2 (962)
HTMLsymbol
Greek small letter final sigma
U+03C3 (963)
HTMLsymbol
Greek small letter sigma
U+03C4 (964)
HTMLsymbol
Greek small letter tau
U+03C5 (965)
HTMLsymbol
Greek small letter upsilon
U+03C6 (966)
HTMLsymbol
Greek small letter phi
U+03C7 (967)
HTMLsymbol
Greek small letter chi
U+03C8 (968)
HTMLsymbol
Greek small letter psi
U+03C9 (969)
HTMLsymbol
Greek small letter omega
U+03D1 (977)
HTMLsymbol
Greek theta symbol
U+03D2 (978)
HTMLsymbol
Greek Upsilon with hook symbol
U+03D6 (982)
HTMLsymbol
Greek pi symbol
HTMLspecial
HTMLspecial
HTMLspecial
U+200C (8204)
HTMLspecial
U+200D (8205)
HTMLspecial
U+200E (8206)
HTMLspecial
U+200F (8207)
HTMLspecial
HTMLspecial
HTMLspecial
HTMLspecial
left single
HTMLspecial
right single
U+201A (8218)
HTMLspecial
single low-9
U+201C (8220)
HTMLspecial
left double
U+201D (8221)
HTMLspecial
right double
U+201E (8222)
HTMLspecial
double low-9
HTMLspecial
HTMLspecial
HTMLspecial
(black small circle)
HTMLsymbol
horizontal
(three dot leader)
HTMLspecial
HTMLsymbol
(minutes, feet)
HTMLsymbol
(seconds, inches)
HTMLspecial
ISO proposed
single left-pointing angle quotation mark
U+203A (8250)
HTMLspecial
ISO proposed
single right-pointing angle quotation mark
U+203E (8254)
HTMLsymbol
(spacing overscore)
HTMLsymbol
fraction slash ()
U+20AC (8364)
HTMLspecial
HTMLsymbol
black-letter capital I (imaginary part)
HTMLsymbol
script capital P (power set, )
U+211C (8476)
HTMLsymbol
black-letter capital R (real part symbol)
HTMLsymbol
HTMLsymbol
(first transfinite cardinal)
HTMLsymbol
leftwards arrow
HTMLsymbol
upwards arrow
HTMLsymbol
rightwards arrow
HTMLsymbol
downwards arrow
HTMLsymbol
left right arrow
U+21B5 (8629)
HTMLsymbol
downwards arrow with corner leftwards (carriage return)
U+21D0 (8656)
HTMLsymbol
leftwards double arrow
U+21D1 (8657)
HTMLsymbol
upwards double arrow
U+21D2 (8658)
HTMLsymbol
rightwards double arrow
U+21D3 (8659)
HTMLsymbol
downwards double arrow
U+21D4 (8660)
HTMLsymbol
left right double arrow
HTMLsymbol
HTMLsymbol
partial differential
HTMLsymbol
HTMLsymbol
(null set); see also
HTMLsymbol
(vector differential operator)
HTMLsymbol
element of
HTMLsymbol
not an element of
U+220B (8715)
HTMLsymbol
contains as member
U+220F (8719)
HTMLsymbol
(product sign)
HTMLsymbol
HTMLsymbol
minus sign
HTMLsymbol
asterisk operator
U+221A (8730)
HTMLsymbol
(radical sign)
U+221D (8733)
HTMLsymbol
proportional to
U+221E (8734)
HTMLsymbol
HTMLsymbol
HTMLsymbol
HTMLsymbol
HTMLsymbol
U+222A (8746)
HTMLsymbol
U+222B (8747)
HTMLsymbol
HTMLsymbol
U+223C (8764)
HTMLsymbol
tilde operator (varies with, similar to)
HTMLsymbol
congruent to
HTMLsymbol
almost equal to (asymptotic to)
HTMLsymbol
HTMLsymbol
sometimes used for 'equivalent to'
HTMLsymbol
less-than or equal to
HTMLsymbol
greater-than or equal to
HTMLsymbol
HTMLsymbol
superset of
HTMLsymbol
not a subset of
HTMLsymbol
subset of or equal to
HTMLsymbol
superset of or equal to
HTMLsymbol
circled plus (direct sum)
HTMLsymbol
circled times (vector product)
U+22A5 (8869)
HTMLsymbol
(orthogonal to, )
U+22C5 (8901)
HTMLsymbol
dot operator
HTMLsymbol
left ceiling (APL upstile)
HTMLsymbol
right ceiling
U+230A (8970)
HTMLsymbol
left floor (APL downstile)
U+230B (8971)
HTMLsymbol
right floor
HTMLsymbol
left-pointing angle bracket (bra)
U+232A (9002)
HTMLsymbol
right-pointing angle bracket (ket)
U+25CA (9674)
HTMLsymbol
HTMLsymbol
HTMLsymbol
(shamrock)
HTMLsymbol
(valentine)
HTMLsymbol
DTD: the full public DTD name (where the character entity name is defined) is actually mapped from one of the following three defined named entities:
HTMLlat1 maps to:
PUBLIC "-//W3C//ENTITIES Latin 1//EN//HTML" in HTML (the DTD is implicitly defined, no system URI is needed);
PUBLIC "-//W3C//ENTITIES Latin 1 for XHTML//EN" "" in XHTML 1.0;
HTMLsymbol maps to:
PUBLIC "-//W3C//ENTITIES Symbols//EN//HTML" in HTML (the DTD is implicitly defined, no system URI is needed);
PUBLIC "-//W3C//ENTITIES Symbols for XHTML//EN" "" in XHTML 1.0;
HTMLspecial maps to:
PUBLIC "-//W3C//ENTITIES Special//EN//HTML" in HTML (the DTD is implicitly defined, no system URI is needed);
PUBLIC "-//W3C//ENTITIES Special for XHTML//EN" "" in XHTML 1.0.
Old ISO subset: these are old (documented) character subsets used in legacy encodings before the unification within ISO 10646.
Description: the standard ISO 10646 and Unicode character name is displayed first for each character, with non-standard but legacy synonyms shown in italics between parentheses after an equal sign.
spaces: a blue background is used to display each space's width.
ligature: this is a standard misnomer as this is a separate character in some languages.
black: here it seems to mean filled as opposed to hollow.
ISO proposed: these characters have been standardized in ISO 10646 after the release of HTML 4.0.
alefsym: 'alef symbol' is not the same as U+05D0 'Hebrew letter alef', although the same glyph could be used to depict both characters.
lArr: ISO 10646 does not say that 'leftwards double arrow' is the same as the 'is implied by' arrow, but also does not have any other character for that function. So lArr can be used for 'is implied by' as ISOtech suggests.
rArr: ISO 10646 does not say that 'rightwards double arrow' is the 'implies' character but does not have another character with this function, so rArr can be used for 'implies' as ISOtech suggests.
prod: 'n-ary product' is not the same character as U+03A0 'Greek capital letter Pi' though the same glyph might be used for both.
sum: 'n-ary summation' is not the same character as U+03A3 'Greek capital letter Sigma' though the same glyph might be used for both.
sim: 'tilde operator' is not the same character as U+007E 'tilde', although the same glyph might be used to represent both.
sup: note that nsup, U+2283 'not a superset of', is not covered by the Symbol font encoding and is not included. Should it be, for symmetry? It is in the ISOamsn subset.
perp: Unicode only defines U+22A5 as the "up tack". The Unicode symbol for "perpendicular" is U+27C2. The two symbols look similar, but are separate in Unicode. However, HTML uses U+22A5 as its "perpendicular" symbol. This is a discrepancy between HTML and Unicode. As well, the U+22A4 character (the "down tack" symbol) rendered in a browser such as
3.6 can match the
of either "up tack" or "perpendicular", but not both, depending on whether a fixed-width or a proportional font is used. When viewed in Firefox 3.6, the symbols rendered in the order U+22A5, U+22A4, U+27C2 in a proportional font: ⊥ ? ? and a fixed width one: ⊥ ? ?, shows that the "down tack" has a similar look to U+22A5 (HTML's "perpendicular") in the first case but matches U+27C2 in the second. This exemplifies the difficulties of the
involved in interpreting ,
generally.
sdot: 'dot operator' is not the same character as U+00B7 'middle dot'.
lang: U+2329 'left-pointing angle bracket' is not the same character as U+003C 'less than', U+2039 'single left-pointing angle quotation mark', U+27E8 'mathematical left angle bracket', or U+3008 'left angle bracket'. In HTML 5.0, lang has been remapped to U+27E8 'mathematical left angle bracket', as U+2329 'left-pointing angle bracket' has been marked deprecated in Unicode ().
rang: U+232A 'right-pointing angle bracket' is not the same character as U+003E 'greater than', U+203A 'single right-pointing angle quotation mark', U+27E9 'mathematical right angle bracket', or U+3009 'right angle bracket'. In HTML 5.0, rang has been remapped to U+27E9 'mathematical right angle bracket', as U+232A 'right-pointing angle bracket' has been marked deprecated in Unicode ().
explicitly declare 253 entities (including the ) whose expansion is a single character, which can therefore be informally referred to as "character entities". These (with the exception of the & entity) have the same names and represent the same characters as the . Also, by virtue of being , XHTML documents may reference the predefined & entity, which is not one of the 252 character entities in HTML. Additional entities of any size may be defined on a per-document basis. However, the usability of entity references in XHTML is affected by how the document is being processed:
If the document is read by a conforming HTML processor, then only the 252 HTML character entities can safely be used. The use of & or custom entity references may not be supported and may produce unpredictable results.
If the document is read by an XML
that does not or cannot read external entities, then only the five built-in XML character entities () can safely be used, although other entities may be used if they are declared in the internal DTD subset.
If the document is read by an XML parser that does read external entities, then the five built-in XML character entities can safely be used. The other 248 HTML character entities can be used as long as the XHTML DTD is accessible to the parser at the time the document is read. Other entities may also be used if they are declared in the internal DTD subset.
Because of the special & case mentioned above, only &, &, &, and & will work in all processing situations.
. See also:
. See also:
The normative reference to
(still found in DTDs defining the character entities for HTML or XHTML) this RFC (along with other RFC's related to different part of the HTML specification) has been deprecated in favor of the newer informational
which defines the "text/html" MIME type and references directly the W3C specifications for the actual HTML content.
at Wikibooks
at the W3C}