Phonetic Symbols Explained: Reading the IPA on Your Child’s Speech Report

✓ Reviewed against International Phonetic Association IPA chart, ASHA Practice Portal, Crowe & McLeod (2020)Evidence level BLast reviewed October 14, 2026Published October 14, 2026

Speech-language pathologists write sounds in the International Phonetic Alphabet (IPA) because English spelling is unreliable: one symbol always means one sound. A few symbols look unfamiliar — /θ/ is the TH in “think,” /ʃ/ is SH, /ŋ/ is NG, and /j/ is the Y in “yes,” not J. This page decodes them.

Why speech reports use phonetic symbols

English spelling is a poor guide to sound. The same letters can spell different sounds (the “th” in “thin” and in “this”), and the same sound can be spelled many ways (“f” in “fish,” “ph” in “phone,” “gh” in “laugh”). American English has 24 consonant sounds — the 24 whose ages of acquisition are reported in Crowe & McLeod’s 2020 review — but only 21 consonant letters.³

The International Phonetic Alphabet solves this with one symbol per sound. It is maintained by the International Phonetic Association, which publishes the official IPA chart. SLPs use it to write down exactly what a child said: ASHA describes transcribing single-word test responses and spontaneous speech samples as part of a speech sound assessment.^1,2

Slashes, brackets, and other notation

/k/ — slashes: the sound as a unit of the language, the sound the word is meant to have.
[k] — square brackets: how the sound was actually pronounced, sometimes with extra detail.
“t/k” — on many reports, a substitution: read it as “t for k.” Conventions vary between clinicians.
[s̪] — a small bridge under a symbol marks a dental sound: an S made with the tongue against the teeth.
[ɬ] — the IPA symbol for a lateral fricative: air escaping over the sides of the tongue, as in a lateral lisp.

The dental diacritic and the lateral fricative symbol are both part of the official IPA chart, which is why they turn up on reports describing lisps.¹

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Ask about anything unclear

A report is written for you as well as for other professionals. If a symbol or abbreviation is not explained, ask the SLP — it is a normal question.

Consonant symbols

Most consonant symbols are ordinary letters with their usual sound. These are the ones that trip parents up.¹

English consonant symbols that differ from spelling (IPA).
Symbol	Sound	As in	Watch out
/θ/	voiceless TH	think, bath	Greek theta
/ð/	voiced TH	this, mother	Not a “d”
/ʃ/	SH	shoe, wish	A long “s” shape
/ʒ/	ZH	measure, beige	A “z” with a tail
/tʃ/	CH	chair, watch	T + SH
/dʒ/	J	jump, giraffe	D + ZH
/j/	Y	yes, yellow	Not the J sound
/ŋ/	NG	sing, ring	One sound, not N + G
/ɹ/	R	red, carrot	Often printed as an upside-down r
/ɡ/	hard G	go, bag	Always the hard G, never the G in “gem”

English consonant symbols that differ from spelling (IPA).¹

The remaining consonants — /p/, /b/, /t/, /d/, /k/, /f/, /v/, /s/, /z/, /h/, /m/, /n/, /l/, /w/ — are written as you would expect. For all 24 with their place, manner, voicing, and typical age, see the consonant sounds chart.³

You will see these symbols in clinical references too. ASHA’s own table of phonological patterns writes its examples in IPA — /tæt/ for “cat” (fronting), /wæbɪt/ for “rabbit” (gliding), /ʃɪp/ for “chip” (deaffrication).⁴

Vowel symbols

Vowel symbols cause the most confusion, because IPA vowels do not follow English spelling at all. These are the General American symbols you are most likely to see.¹

Common English vowel symbols (General American, IPA).
Symbol	As in	Symbol	As in
/i/	beet	/u/	boot
/ɪ/	bit	/ʊ/	book
/ɛ/	bet	/ɔ/	thought
/æ/	bat	/ɑ/	father
/ʌ/	but	/ə/	about (schwa)
/ɝ/	bird	/ɚ/	butter (unstressed)
/eɪ/	bait	/oʊ/	boat
/aɪ/	bite	/aʊ/	bout
/ɔɪ/	boy

Common English vowel symbols (General American, IPA).¹

Vowels are usually accurate early — in one study of 314 American children, vowel errors were minimal (0–4%) in typically developing children from age 3 — so vowel symbols on a report for an older child are worth asking about.⁵

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Accents change the vowels

The symbols above are for General American English; British, Australian, and Indian English use some different vowels. ASHA is explicit that accents are not a communication disorder, and an SLP transcribes against the child’s own community’s pronunciation.

ASHA’s Practice Portal notes that the SLP needs to know how the child’s linguistic community pronounces a word when judging whether it was said correctly.^6,2

Reading the rest of a speech report

Process names (fronting, stopping, gliding, cluster reduction): the error patterns your child uses — see the phonological processes chart for each one’s typical age.
PCC (percentage of consonants correct): a severity measure calculated from a transcribed speech sample.
Stimulable: your child can say the sound correctly when given a model to copy.
Initial / medial / final: where in the word the sound falls — start, middle, or end.

ASHA describes PCC as a quantitative approach to severity: the SLP transcribes a speech sample, counts the consonants, and works out the percentage produced correctly. It describes stimulability as a child’s ability to imitate a model of a sound they currently get wrong, tested in contexts such as isolation, syllables, words, and phrases.²

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If you do not have a report yet

Phonetic transcription is part of a full speech evaluation by a speech-language pathologist. If you are concerned about how your child says sounds, you can find a certified SLP through ASHA’s ProFind directory. Children who have trouble producing speech sounds correctly may have a speech disorder, and ASHA notes that differences rooted in a child’s dialect are not one.^9,8,7

Frequently asked questions

Why do speech therapists use phonetic symbols?＋

Because English spelling does not map neatly onto sounds — the 24 English consonant sounds are written with 21 consonant letters, and letters such as c, q, and x have no sound of their own. The International Phonetic Alphabet gives each sound one symbol, which lets an SLP write down exactly what a child said. ASHA describes SLPs phonetically transcribing speech samples during assessment.

What is the difference between /k/ and [k]?＋

Slashes mark a sound as a unit of the language — the sound the word is supposed to have (/k/ in “cat”). Square brackets mark how a sound was actually pronounced, often with extra detail. A report might say a child produces /s/ as [θ]: the target S came out as a TH-like sound, the classic frontal lisp.

Is /j/ the J sound?＋

No — this is the most common surprise for parents. In the IPA, /j/ is the Y sound in “yes.” The J sound in “jump” is written /dʒ/, a D-plus-ZH combination, and the CH in “chair” is /tʃ/.

What does “t/k” mean on a speech report?＋

Many reports use a slash to record a substitution — typically read as “t for k,” meaning the child said T where K belongs (as in “tat” for “cat,” the pattern called fronting). Conventions vary between clinicians, so if a notation is unclear, ask the SLP who wrote it.

What is PCC on a speech report?＋

PCC stands for percentage of consonants correct. ASHA describes it as a quantitative way to rate severity: the SLP phonetically transcribes a speech sample, counts the consonants, and calculates the share produced correctly.