Esperanto letter J

The Esperanto letter J (called jo in Esperanto) represents IPA phoneme /j/, a semiconsonant.

At the beginning of the syllable
At the beginning of the syllable Esperanto "j" sounds like English "y" in "yes" or "young".
 * jaro (year); jes (yes); junulo (young person); lernejo (school); objekto (object); vojaĝo (trip); vojo (way)

At the end of the syllable
If we make an analogy with Ŭ, "j" can be rendered as /i&#x032F;/. In this case "j" is a semivowel that can form the diphthongs aj, ej, oj and uj.

aj
Like English /aɪ/ as in "night" /naɪt/.

ej
Like English /eɪ/ as in "date" /deɪt/.

oj
Very similar to English /ɔɪ/ as in "boy" /bɔɪ/.

uj
The sequence "uj" (as in kiuj) instead of /ui&#x032F;/ (or (uj) may be heard as /wi/. Kiuj should be pronounced as /kiui&#x032F;/ (secondary stress in the "u"), however it may be heard as /kiwi/ (secondary stress in the second "i"). See Lernu for more opinions.