Obsolete and nonstandard symbols in the International Phonetic Alphabet

The International Phonetic Alphabet (IPA) possesses a variety of obsolete and nonstandard symbols. Throughout the history of the IPA, characters representing phonetic values have been modified or completely replaced. An example is ⟨ɷ⟩ for standard [ʊ]. Several symbols indicating secondary articulation have been dropped altogether, with the idea that they should be indicated with diacritics: ʮ for z̩ʷ is one. In addition, the rare voiceless implosive series ƥ ƭ 𝼉 ƈ ƙ ʠ has been dropped.

Other characters have been added in for specific phonemes which do not possess a specific symbol in the IPA. Those studying modern Chinese phonology have used ⟨ɿ⟩ to represent the sound of -i in Pinyin hanzi which has been variously described as [ɨ], [ɹ̩], [z̩] or [ɯ]. (See the sections Vowels and Syllabic consonants of the article Standard Chinese phonology.)

There are also unsupported symbols from local traditions that find their way into publications that otherwise use the standard IPA. This is especially common with affricates such as ƛ, and many Americanist symbols.

While the IPA does not itself have a set of capital letters (the ones that look like capitals are actually small capitals), many languages have adopted symbols from the IPA as part of their orthographies, and in such cases they have invented capital variants of these. This is especially common in Africa. An example is Kabiyé of northern Togo, which has Ɔ Ɛ Ŋ Ɣ. Other pseudo-IPA capitals supported by Unicode are Ɓ/Ƃ Ƈ Ɗ/Ƌ Ə/Ǝ Ɠ Ħ Ɯ Ɲ Ɵ Ʃ (capital ʃ) Ʈ Ʊ Ʋ Ʒ. (See Case variants of IPA letters.)

Capital letters are also used as cover symbols in phonotactic descriptions: C=Consonant, V=Vowel, N=Nasal, S=Sonorant, etc.

This list does not include commonplace extensions of the IPA, such as doubling a symbol for a greater degree of a feature ([aːː] extra-long [a], [ˈˈa] extra stress, [kʰʰ] strongly aspirated [k], and [a˞˞] extra-rhotic [a]), nor superscripting for a lesser degree of a feature ([ᵑɡ] slightly prenasalized [ɡ], [ᵗs] slightly affricated [s], and [ᵊ] epenthetic schwa). The asterisk, as in [k*] for the fortis stop of Korean, is the convention the IPA uses when it has no symbol for a phone or feature.

For symbols and values which were discarded by 1932, see History of the International Phonetic Alphabet.

Obsolete and/or nonstandard symbols in the International Phonetic Alphabet

Symbol or exemplar	Name	Meaning	Standard IPA equivalent	Notes
?	question mark	glottal stop	ʔ	typewriter substitution
7	digit seven	glottal stop	ʔ	typewriter substitution
'	apostrophe	glottal stop	ʔ	typewriter substitution
q	q	glottal stop	ʔ	used in Maltese, Khmer and Malayo–Polynesian languages transcriptions.
φ	Greek phi	voiceless bilabial fricative	ɸ	a mistake, typewriter substitution or similarity of shape
ψ	Greek psi	retroflex click	𝼊, ‪‼	used by (Doke 1925)
		bunched-r	ɹ̈	proposed by John Laver (1994)
ß	sharp s	voiced bilabial fricative	β	a mistake, typewriter substitution or similarity of shape
∫, ⌠ ⌡ or$\displaystyle \int$	integral symbol	voiceless postalveolar fricative	ʃ	a mistake, typewriter substitution or similarity of shape
3	digit three	voiced postalveolar fricative	ʒ	a mistake, typewriter substitution or similarity of shape; often confused with open-mid central unrounded vowel
đ	d with stroke	voiced dental fricative	ð	a mistake, typewriter substitution or similarity of shape
þ	thorn	voiceless dental fricative	θ	a mistake
ƍ	turned delta	labialized voiced alveolar or dental fricative	ðʷ, zʷ, z͎	intended for the voiced whistled sibilant, ɀ, of Shona and related languages, withdrawn 1976
σ	sigma	labialized voiceless alveolar or dental fricative	θʷ, sʷ, s͎	intended for the voiceless whistled sibilant, ȿ, of Shona and related languages, withdrawn 1976
ƺ	ezh with tail	labialized voiced postalveolar fricative	ʒᶣ, ʑʷ	intended for w before front vowels in Twi; may also be used for the lightly rounded English /ʒ/, withdrawn 1976.
ƪ	reversed esh with top loop	labialized voiceless postalveolar fricative	ʃᶣ, ɕʷ	intended for hw before front vowels in Twi; may also be used for the lightly rounded English /ʃ/, withdrawn 1976.
ƻ	barred digit two	voiced alveolar affricate	d͡z	withdrawn 1976
ƾ or ʢ	turned voiced epiglottal trill	voiceless alveolar affricate	t͡s	withdrawn 1976
ƞ	eta	moraic nasal	m, n, ŋ, ɴ̩	Intended for the moraic nasal /N/ of Japanese. Withdrawn 1976
◌̡ (ᶀ ᶁ ᶂ ᶃ ꞕ ᶄ ᶅ 𝼓 ᶆ ᶇ 𝼔 ᶈ ᶉ 𝼕 𝼖 ᶊ ᶋ ƫ ᶌ ᶍ ᶎ 𝼘)	palatal hook	palatalization	bʲ dʲ fʲ ɡ̟ hʲ k̟ lʲ ɬʲ mʲ nʲ ŋ̟ pʲ rʲ ɹʲ ɾʲ sʲ ɕ tʲ vʲ x̟ zʲ ʑ	Typically used in the transcription of Slavic languages such as Russian. Superseded 1989
◌̢	retroflex hook	voiced alveolar or retroflex approximant	ɹ / ɻ	a mistake; an example like /ᶚ/ was actually [ʒ͡ɻ]
◌̢	retroflex hook	r-colored vowels	ɝ, ɚ or ɜ˞, ə˞	Superseded 1989; MODIFIER LETTER RHOTIC HOOK (U+02DE) is now preferred
	unstressed central rhotic vowel	r-colored vowel in American English	ɝ, ɚ or ɜ˞, ə˞	Proposed in 1934, MODIFIER LETTER RHOTIC HOOK (U+02DE) is now preferred
ʃ ʒ t͡ʃ d͡ʒ		alveolo-palatal consonants	ɕ, ʑ, t͡ɕ, and d͡ʑ; respectively	broad transcription; especially Japanologists and Koreanists
a	a		any open vowel	Often a substitute for ɑ in printing when the distinction between a and ɑ is not needed.
ɑ	Latin alpha		any open vowel	Often a substitute for ɑ in printing when the distinction between a and ɑ is not needed.
a	reversed a	near-open front unrounded vowel	æ	Proposed in 1989, rejected
c	c		t͡ʃ, t͡ɕ or sometimes t͡s.	broad transcription
	nv ligature	close front rounded vowel	y	proposed in 1989, rejected
ᵿ˞	barred horseshoe u with hook	back sulcal vowel		proposed in 1989, rejected
	w with left hook	voiced labial-velar fricative (labialized voiced velar fricative)	ɣʷ	proposed in 1989, rejected
or 𝼥 𝼦 𝼧 𝼨 𝼪	letters with left-swinging top hook	dental consonants	d̪ l̪ n̪ r̪ t̪	proposed in 1989, rejected; Malayalam transcriptions
	long-leg g	voiced velar lateral approximant	ʟ	proposed in 1989, rejected
ꝣ	hooktop ezh	voiced velar fricative	ɣ	proposed in 1989, rejected
	double-loop g	voiced velar fricative	ɣ	from 1895 to 1900, [q] represented that consonant before 1895, [ǥ] after 1900
	double-loop g	voiced velar plosive	ɡ	standard Unicode Basic Latin/ASCII lower-case g (U+0067) may have a double-loop g glyph. the preferred IPA single-loop g (U+0261) is in the IPA Extensions Unicode block. for a time it was proposed that the double-loop g might be used for [ɡ] and the single-loop g for [ᶃ] (ɡ̟), but the distinction never caught on.
	double-loop g	voiced postalveolar affricate	d͡ʒ	used in Arabic transcriptions
	single-loop g with stroke	voiced velar fricative	ɣ	replaced double-loop g in 1900, then replaced by gamma [ɣ] around 1928-1930. the character ǥ may not have the single-loop shape in some fonts.
j	j		d͡ʒ, d͡ʑ or sometimes d͡z
ɟ	barred dotless small j (or turned f in some fonts)		d͡ʒ or d͡ʑ
k̫ ɡ̫ m̫ x̫ p̫ ʒ̫ etc.	subscript w	labialization	kʷ ɡʷ mʷ ʍ pʷ ʒʷ etc.	mark may appear above letters with descenders like [ɡ] or [ŋ]. removed 1989
ʆ	curly-tail esh	voiceless alveolo-palatal fricative	ɕ	variant, also for Russian щ (now ⟨ɕ⟩). removed 1989
ʓ	curly-tail ezh	voiced alveolo-palatal fricative	ʑ	variant, removed 1989
ȵ, ȡ, ȶ, ȴ	curly-tail n, d, t, l	alveolo-palatal consonants	n̠ʲ, d̠ʲ, t̠ʲ, l̠ʲ or ɲ̟, ɟ˖, c̟, ʎ̟	used by some Sinologists.
ř	r with háček	voiced strident apico-alveolar trill	r̝	Intended for ř in Czech and related languages. ⟨ř⟩ from 1909, replaced by ⟨ɼ⟩ in 1949, Withdrawn 1989
ɼ	long-leg r	voiced strident apico-alveolar trill	r̝	Intended for ř in Czech and related languages. ⟨ř⟩ from 1909, withdrawn 1989.
ɼ	long-leg r	syllabic alveolar trill	r̩	a mistake
λ ()	Greek lambda	voiced palatal lateral approximant	ʎ	a mistake
		voiced alveolar lateral affricate	d͡ɮ	used by Americanists
ƛ	barred lambda	voiceless alveolar lateral affricate	t͡ɬ	used by Americanists
ł	l with stroke	voiceless alveolar lateral fricative	ɬ	used by Americanists, also a typographic substitute
ł	l with stroke	velarized voiced alveolar lateral approximant	ɫ	used by Baltic transcriptions
ᴫ	small capital Cyrillic el	voiced uvular lateral approximant	ʟ̠
š č ž	s c z with háček	postalveolar consonants	ʃ t͡ʃ ʒ; ʂ ʈ͡ʂ ʐ	used by Americanists, Uralicists, Semiticists, Slavicists
ǰ, ǧ, ǯ	j, g, ezh with háček	voiced postalveolar affricate	d͡ʒ; ɖ͡ʐ	used by Americanists, Slavicists
ć ĺ ń ś ź dź	c l n s z dz with acute accent	alveolo-palatals or palatals and postalveolar consonants	t͡ɕ l̠ʲ n̠ʲ ɕ ʑ d͡ʑ; t͡ʃ ʎ ɲ ʃ ʒ d͡ʒ	used by Slavicists
x, ɣ	x, Latin gamma	voiceless and voiced uvular fricative (or voiced uvular approximant)	χ, ʁ or χ, ʁ̞	broad transcriptions in Hindi, Arabic and Hebrew transcriptions
ẋ	x with dot	voiceless uvular fricative	χ	used by Americanists
X	uppercase x	voiceless uvular fricative	χ	a mistake
Y	uppercase y	voiced labial–palatal approximant	ɥ	a mistake
	baby gamma	close-mid back unrounded vowel	ɤ	used from 1921 to 1989, replaced by ramshorn to avoid confusion with gamma ; LATIN SMALL LETTER RAMS HORN (U+0264) now represents both glyphs
ρ	rho	bilabial trill	ʙ	common before an official letter was adopted
ɉ	barred j	voiced post-palatal approximant	ȷ̈
ɥ̵	barred turned h	compressed voiced post-palatal approximant	ɥ̈
w̶	barred w	protruded voiced post-palatal approximant	ẅ
ᵻ / ᵿ	barred small capital i / upsilon	near-close central unrounded / rounded vowel	ɪ̈ / ʊ̈, ɨ̞ / ʉ̞, ɘ̝ / ɵ̝	used by some English phoneticians, including the Oxford English Dictionary
ʚ	closed epsilon	open-mid front rounded vowel	œ	alternate symbol from 1904-1920s
ʚ	closed epsilon	open-mid central rounded vowel	ɞ	removed 1996
ɩ	Latin iota	near-close near-front unrounded vowel	ɪ	longstanding alternate symbol until 1989
ı	dotless small i	near-close near-front unrounded vowel	ɪ	a mistake or typographic substitute; or used by Americanists.
ȸ ȹ	db and qp ligatures or footless phi and headless phi	voiced and voiceless labiodential plosives	b̪ p̪	Used by Africanists.
0, ∅, or Ø	digit zero, slashed digit zero or uppercase slashed o	null initial		usually used in phonology to mean a spelling with no sound value. however, in Chinese and some Korean linguistics, some scholars use it for a weak glottal stop; the sound value of the first consonant of syllables started by a vowel.
ƥ ƭ 𝼉 ƈ ƙ ʠ	hooktop p, t, ʈ, c, k, q	voiceless implosives	ɓ̥ ɗ̥ ᶑ̊ ʄ̊ ɠ̊ ʛ̥ or pʼ↓ tʼ↓ ʈʼ↓ cʼ↓ kʼ↓ qʼ↓	brief additions to the IPA; removed 1993
ʇ	turned t	dental click	ǀ	removed 1989; see click letters
ʗ	stretched (or descended) c	alveolar click	ǃ	removed 1989; see click letters
ʖ	turned pharyngeal fricative	alveolar lateral click	ǁ	removed 1989; see click letters
ʞ	turned k	originally a palatal click, reinterpreted as a velar click		velar articulation was judged impossible. later reanalyzed and found paralinguistically. For several years used for a voiceless velodorsal stop in the extIPA.
𝼋 (⨎)	esh with two bars	fricated palatal click	ǂǂ or ǃ͡s	uncommon letter in Ekoka !Kung transcription
⦀	triple vertical bar	retroflex lateral click	ǁ˞
ȣ	ou	close-mid back unrounded vowel or voiced velar fricative	ɤ or ɣ	a common mistake
r	r	alveolar trill	any rhotic sound (including r-colored vowels)	broad transcription
ʀ or R	small capital or uppercase r	long vowel or prolonged moraic N	ː	used by Japanologists. This symbol represents phonemic long vowel (such as /aʀ/) or /aR/) or rarely prolonged moraic N (hatsuon).
ᴙ	reversed small capital r	voiced epiglottal trill	ʀ̠ or ʢ	rare
ɿ	dotless long i with fishhook	syllabic denti-alveolar approximant	ɹ̩, ɹ̩, z̩, ◌͡ɯ	used by Sinologists, and by Japanologists specifically for the Miyako and Tarama languages.
ʅ	dotless long i with fishhook and tail	syllabic retroflex approximant	ɹ̩, ɻ̩, ʐ̩, ◌͡ɨ	used by Sinologists. See Chinese vowels
ʮ	turned h with fishhook	labialized syllabic denti-alveolar approximant	ɹ̩ʷ, z̩ʷ, ◌͡u	used by Sinologists
ʯ	turned h with fishhook and tail	labialized syllabic retroflex approximant	ɻ̩ʷ, ʐ̩ʷ, ◌͡ʉ	used by Sinologists
ᴀ	small capital a	open central unrounded vowel	ä, a̠, ɑ̈, ɑ̟, ɐ̞	used by Sinologists
ᴀ	small capital turned a	close-mid back unrounded vowel	ɤ	withdrawn in 1928.
ꬰ	barred Latin alpha	open central unrounded vowel	ä, a̠, ɑ̈, ɑ̟, ɐ̞	used by Teuthonista
ᴇ	small capital e	mid front unrounded vowel	e̞, ɛ̝	Bloch & Trager (1942). Used by Sinologists and some Koreanists
ꬳ	barred e	close-mid central unrounded vowel	ɘ	used by Teuthonista
ⱻ	small capital turned e	mid back unrounded vowel	ɤ̞, ʌ̝	used by some Koreanists who study Gyeongsang dialect, where there is no phonemic differentiation between /ʌ/ (RR eo; Hangul ㅓ) and /ɯ/ (RR eu; Hangul ㅡ).
ɷ	closed omega	near-close near-back rounded vowel	ʊ	longstanding alternate symbol until 1989
ω	omega	near-close near-back unrounded vowel	ɯ̽ or ʊ̜	made from obsolete ɷ symbol.
ω	omega	near-open back rounded vowel	ɒ̝, ɔ̞	used by Sinologists ; also Bloch & Trager (1942).
ꭥ	small capital omega	mid back rounded vowel	o̞, ɔ̝	Used by Sinologists and some Koreanists ; also Bloch & Trager (1942).
ꝋ	barred o	close-mid central rounded vowel	ɵ	used by Teuthonista
ᴜ	small capital u	near-close near-back rounded vowel	ʊ, ʊ̹	Americanist notation
ᵾ	barred small capital u	near-close central rounded vowel	ʊ̈, ʉ̞, ɵ̝	Americanist notation
B G Ɠ H I L Ɬ N Œ R Y	uppercase letters	small caps	ʙ ɢ ʛ ʜ ɪ ʟ 𝼄 ɴ ɶ ʀ ʏ	often mistaken by typing, uppercase alternatives to symbols shaped like small capitals
ꞯ	small capital q	pharyngeal stop	ʡ	proposed for the pharyngeal stop of Formosan languages, ExtIPA for same purpose.
ꞯ	small capital q	sokuon		used by Japanologists.
Q	capital Q			used by Japanologists.
l	l	all coronal liquid consonants.		broad transcription, mainly Koreanologists.
ꞎ 𝼆 𝼄	belted letters	voiceless lateral fricatives (retroflex, palatal, velar, and alveolar)	ɭ̊˔ ʎ̝̊ ʟ̝̊	now in the extIPA
ʎ	turned y	alveolo-palatal lateral approximant	[ʎ̟] or [l̠ʲ]	broad transcription, mainly Koreanologists and Sinologists
ɲ	n with left hook	alveolo-palatal nasal	[ɲ̟] or [n̠ʲ]	broad transcription, mainly Koreanologists, Sinologists, and Japanologists
ⱳ	w with hook	bilabial flap	ⱱ̟
𝼈	turned r with long leg and retroflex hook	retroflex lateral flap	ɭ̆
ᶘ ᶚ	esh or ezh with retroflex hook	retroflex palato-alveolar fricatives	ʃ͡ɻ ʒ͡ɻ	may be impossible to pronounce
ɏ	barred y	close central compressed vowel	ÿ
ɏ	small capital barred y	near-close central compressed vowel	ʏ̈
ұ	barred straight y (Cyrillic straight u)	near-close near-back unrounded vowel	[ʊ̜] or [ɯ̽]	used in Mande studies
◌̣	underdot	retroflex or r-colored vowels	ɑ˞ o˞ etc.
k', t', etc.	apostrophe	no audible release	k̚, t̚, etc.	removed
k', t', etc.	apostrophe	palatalization	k̟, tʲ, etc.	common in X-SAMPA
K T etc.	uppercase letters (not small capitals)	fortis	k͈ t͈, etc.	used by some Koreanologists
ɔ̩	vowel with tilted line below	lower-pitched rising / falling tone contour		for languages that distinguish multiple rising or falling tones
kʻ tʻ	turned comma above	weak (sometimes normal) aspiration	k t (sometimes kʰ tʰ)	First symbol may be left single quotation mark (U+2018) or modifier letter apostrophe (U+02BC); second symbol may be single high-reversed-9 quotation mark (U+201B) or modifier letter reversed comma (U+02BD)
ʦ ʣ ʧ ʤ ꭧ ꭦ ʨ ʥ	ligatures	affricates	t͡s d͡z t͡ʃ d͡ʒ ʈ͡ʂ ɖ͡ʐ t͡ɕ d͡ʑ	formerly acceptable variants
𝼗 𝼒	ligatures with palatal hook	palatalized affricates	t͡ʃʲ d͡ʒʲ
𝼜 𝼙	ligatures with retroflex hook	retroflex affricates	t͡ʂ d͡ʐ	John Laver used 𝼜 in Polish transcription
p′ s′ t′ etc.	prime	palatalization	pʲ sʲ tʲ etc.	traditional Irish phonology transcription
pʼ sʼ tʼ etc.	combining apostrophe	palatalization	pʲ sʲ tʲ etc.	traditional Russian phonology transcription
*	asterisk	syntactic gemination	(none)	used in some Italian dictionaries
˹	open corner	release/burst	(none)	IPA number 490
d d͡ɮ d͡z l ɫ ɬ ɮ n r ɹ ɾ s t t͡ɬ s z	without diacritics	dental consonants	d̪ d̪͡ɮ̪ d̪͡z̪ l̪ ɫ̪ ɬ̪ ɮ̪ n̪ r̪ ð̞ ɾ̪ s̪ t̪ t̪͡ɬ̪ t̪͡s̪ z̪	broad transcriptions; in some English dialects, /ð̞/ often described as ⟨ɹ̪⟩ for /r⁓ɹ/
β ð ʝ ɣ ʁ ʕ or e ø ɘ ɵ ɤ o	without diacritics	approximant consonants or mid vowels	β̞ ð̞ j ɰ ʁ̞ ʕ̞ or e̞ ø̞ ə ɵ̞ ɤ̞ o̞	broad transcriptions; in Spanish, /j/ and /ɰ/ often described as ⟨ʝ̞⟩ and ⟨ɣ̞⟩
ɛ œ ɜ ɞ ʌ ɔ	without diacritics	mid vowels	e̞ ø̞ ə ɵ̞ ɤ̞ o̞	broad transcriptions; for example in some languages, /e̞/ and /o̞/ maybe described as ⟨ɛ̝⟩ and ⟨ɔ̝⟩, also /ə/ maybe described as ⟨ɘ̞⟩ or ⟨ɜ̝⟩
ɪ ʊ a ɒ	without diacritics	central vowels	ɪ̈ ʊ̈ ä ɒ̈	broad transcriptions; in some English dialects, /ä/ often described as ⟨ɑ̈⟩ in English for /ɑ/
c or ȼ	c or stroked c	voiceless alveolar affricate	t͡s	Americanist notation
ʒ	ezh	voiced alveolar affricate	d͡z	Americanist notation
y	y	voiced palatal approximant	j	Americanist notation
ä	a with diaeresis	near-open front unrounded vowel, open-mid front unrounded vowel or open front unrounded vowel	æ, ɛ or a	Uralicist notation
ö	o with diaeresis	close-mid front rounded vowel, open-mid front rounded vowel or mid front rounded vowel	ø, œ or ø̞	Americanist and Uralicist notation
ü	u with diaeresis	close front rounded vowel or near-close near-front rounded vowel	y or ʏ	Americanist and Uralicist notation
k’ t’ etc.	right single quotation mark	Korean fortis	k͈ t͈ etc.	used by some Koreanists for fortis sounds; equivalent to ⟨k*⟩, etc. above.
◌⸋	box	unreleased	◌̚	used where IPA ◌̚ would get confused with the corners used to indicate change of pitch in the Japanese pitch accent system
◌ʱ		breathy/ voiced aspiration	◌̤
◌ˀ		creaky voice/ glottalization	◌̰
◌̴		velarization	◌ˠ
ˉ◌, ˗◌, ˍ◌		high, mid and low-level tone or intonation		removed
˭◌, ₌◌		extra-high and extra-low level tone or intonation		removed
ˋ◌, ˴◌, ˎ◌		falling or high falling, mid falling and low-falling tone or intonation		removed
ˊ◌, [NA], ˏ◌		(high) rising and low rising tone or intonation		removed
ˇ◌, ˬ◌		(high) dipping and low dipping (falling-rising) tone or intonation		removed
ˆ◌, ꞈ◌		peaking (rising-falling) tone or intonation		removed
˜◌, ̰◌		"wavy" tone or intonation		removed
˙◌, ·◌, .◌		atonic syllable with high, mid, and low pitch; respectively		removed
◌́, ◌̂, ◌̀, ◌̆	Acute accent, circumflex, grave accent, breve	stress symbols: primary stress, weakened primary stress, secondary stress, and no stress; respectively	ˈˈ◌, ˈ◌, ˌ◌, ◌	some English phoneticians and phonologists use acute and grave accents as primary and secondary stress symbols. Some linguists use the circumflex as weakened primary stress in compound words and the breve as no stress. these symbols are also written on the English spellings not just other IPA symbols.
◌̩, ◌̍	Vertical line below or above	moraic		used by Japanologists. In the standard IPA, these symbols represents syllabic sounds, but Japanologists use them for phonetic variants (except for nasal vowels) of the moraic N ([n̩, ɴ̩, ŋ̍ (or ŋ̩), m̩]).
◌̄, ◌́, ◌̌, ◌̀	Macron, acute accent, caron, grave accent	Chinese tones	◌́, ◌̌, ◌̀, ◌̂ or similar, depending on dialect and analysis, or Chao tone letters	used by Sinologists with the values the symbols have in Hanyu Pinyin. the standard IPA values of these diacritics are: mid, high, rising, and low tone.

See also

• History of the IPA
• Americanist phonetic notation
• Uralic Phonetic Alphabet