The following tables show IPA and X-SAMPA representations of Classical Nahuatl pronunciation. Examples are shown using modern standardized spelling, situations arising from varying spellings are explained in the footnotes.
↑ 1.01.11.21.3Long vowels were rarely marked in historical manuscripts. Vowel length is indicated with a macron in modern standardized spelling, as long vowels and short vowels are not allophones of each other, and therefore differentiated.
↑ 2.02.1Both /o/ and /oː/ were sometimes represented by u in manuscripts (e.g. teutl for teōtl, etc.).
^Written cu in all positions or cuhpostvocalically in manuscripts (e.g. tecutli or tecuhtli for tēuctli). Inversion to uc after vowels is conventional in modern spelling. The qu in manuscript spellings such as quauhtli (cuāuhtli in modern spelling) also corresponds to this sound.
↑ 2.02.1/l/ and /lː/ are found only found in the syllable onset.
↑ 3.03.13.2Sometimes transcribed /ll/, /ss/ and /ʃʃ/, with one consonant belonging to the first syllable's coda and the other to the next syllable's onset. However, these encounters are more accurately represented by /lː/, /sː/ and /ʃː/, as the encounter between two akin sibilants or approximants in Classical Nahuatl leads to a lengthened consonantal sound rather than a pair of identical sounds.
^[ɬ] is an allophone of /l/ at the end of the syllable coda.
^Primary stress in Classical Nahuatl almost always falls on the penult. The only exceptions are vocative forms, which always stress the final syllable (when male speakers use the vocative they add the suffix -é to the absolutive ending, replacing the final i if present, while female speakers simply stress the last syllable).
^The stressed syllable also receives a raised pitch accent, which can be shown in IPA as an acute accent (´invalid IPA characters (´)) on the vowel of the stressed syllable.