The ProHi uses the International Phonetic Alphabet (IPA), a system of phonetic representation in which each symbol represents a single sound in speech.

There are many dialects, or varieties, of English around the world. The current ProHi uses Mainstream North American English with the first pronunciation listed by the Carnegie Mellon University Pronouncing Dictionary. Even within North America, there are many varieties of English. Carnegie Mellon University is located in Pittsburgh, Pennsylvania.

Learners can use the ProHi themselves to identify words containing target sounds (consonants or vowel sounds that they are working on pronouncing accurately) in contexts that are relevant to them. For example, a student about to give an oral presentation on a topic of erosion and who is conscious that they have trouble pronouncing the sound /ʒ/ can input their presentation notes into the ProHi and search for all instances of /ʒ/. Words such as “erosion,” “usually,” and “measure” will appear highlighted, and the student can rehearse those words before giving the presentation. Also, teachers and materials developers can use the tool for lesson planning and preparation purposes.

Both are speech sounds. A consonant is produced with parts of the vocal tract making contact with one another (for example, the top and bottom lips making contact for the /m/ sound) or constricting the airstream (for example, the top and bottom lips rounding into a small tight circle for the /w/ sound). In contrast, a vowel is produced without an obstruction of the airstream; no parts of the vocal tract come in contact (for example, the /o/ sound in “so”).

No. It is impossible to list all the sounds of English in alphabetical order, because the letters of the English (Roman) alphabet don’t correspond one-to-one with the sounds of English. The symbols in the ProHi are organized by the place in the mouth where the sound is articulated. This is helpful when learning how to pronounce the consonants and vowels.

Consider the consonant chart.

The top row of the consonant chart includes all the phonemes produced by a closure or partial closure of the lips. The second row lists those phonemes produced by a closure or partial closure of the lip plus teeth. Next comes the interdental sounds, then the sounds made with the alveolar ridge, then the palatal-alveolar area, then the velum (soft palate), and finally the glottis. From left to right, the phonemes progress from one manner of articulation to another. The leftmost column is voiceless, whereas the second column is voiced. Nasal sounds occupy the third column, and approximants occupy the rightmost column.

The vowel chart is likewise very intentional in its design.

The vowel chart is a representation of where the tongue is located in the mouth when pronouncing the vowel. Imagine that there are teeth and lips to the left of the chart, and the throat to the right of the chart. Three columns (from left to right) represent the front, middle, and back of the mouth. Five rows represent the height of the tongue (from high to low). The bottom row, offset a bit from the others, lists the diphthongs, that is, vowel sounds that fit into one syllable but require the tongue to travel from a starting point to a different ending point, such as the diphthong /ɔi/ as in the word “boy”, which starts as a low back vowel and ends as a high front vowel.

It is possible that this word is not yet in the ProHi dictionary, or that there is an error. Please report it using the “Report Word-Specific Issue” at the bottom of the page so we can fix it.

It is also possible that the sound you hear is represented by a different phoneme than the one you expect.

If you are looking for the consonant /r/, try searching for the vowel /ɝ/ as well.

If you are looking for the vowel /ɑ/, try searching for the vowel /ɔ/ as well. (Most speakers of North American English don’t differentiate those sounds.)

If you are looking for the consonant /w/, try the vowels /ao/ or /u/ or /o/ as well.

If you are looking for the consonant /j/, try the vowels /i/ or /e/ or /aɪ/ or /ɔɪ/ as well.

Each consonant and vowel appearing in the ProHi charts is a phoneme. A phoneme is a speech sound that can distinguish one word from another. Therefore it has high priority for language learners. The inventory of phonemes differs from language to language and even from dialect to dialect. For example, two of the phonemes of Mainstream North American English are /w/ and /v/, because “wet” (the opposite of dry) and “vet” (veterinarian or veteran) are different words and mean very different things. However, in many languages of India, for instance, /w/ and /v/ are not distinct phonemes.

The ProHi does not list the allophones of North American English. Allophones are different realizations of the same phoneme, but don’t distinguish one word from another. In Mainstream North American English, “water” (pronounced with a voiceless, aspirated alveolar stop consonant in the middle of the word, as in some British English varieties) and “water” (pronounced with a voiced alveolar flap similar to the sound of /d/) are the same word, meaning H20, because /t/ and /ɾ/ are not two distinct phonemes in this dialect, but two realizations of the same phoneme. Another allophone, the glottal stop found in the middle of the words “button” and “uh-oh,” is not listed either.