Wells is known for his book and cassette Accents of English, the book and CD The Sounds of the IPA, Lingvistikaj Aspektoj de Esperanto, and the Longman Pronunciation Dictionary. He is the author of the most widely used English-Esperanto dictionary.
Before writing Accents of English, Wells had written a very critical review of the Linguistic Atlas of England, which was the principal output of the Survey of English Dialects. He argued that the methodology was outdated, that the sample was not representative of the population and that it was not possible to "discover with any certainty the synchronic vowel-system in each of the localities investigated".
Wells has long been a pioneer of new technology. He is the inventor of the X-SAMPA ASCII phonetic alphabet for use in digital computers that could not handle IPA symbols. He learned HTML during the mid-1990s, and he created a Web page that compiled media references to Estuary English, although he was sceptical of the concept. After retirement, Wells ran a regular blog on phonetic topics from March 2006 to April 2013. He announced the end of his blog on 22 April 2013 saying, "if I have nothing new to say, then the best plan is to stop talking."
Longman Pronunciation Dictionary
Wells was appointed by Longman to write its pronunciation dictionary, the first edition of which was published in 1990. There had not been a pronunciation dictionary published in the United Kingdom since 1977, when Alfred C. Gimson published his last (the 14th) edition of English Pronouncing Dictionary. The book by Wells had a much greater scope, including American pronunciations as well as RP pronunciations and including non-RP pronunciations widespread in Great Britain (such as use of a short vowel in the words bath, chance, last, etc. and of a long vowel in book, look, etc.). His book also included transcriptions of foreign words in their native languages and local pronunciations of place names in the English-speaking world.
Wells was president of the Spelling Society, which advocates spelling reform, from 2003 to 2013. He was criticised in a speech by David Cameron for advocating tolerance of text spelling and omitted apostrophes.
In Accents of English he defined the concept of lexical sets, a concept in wide usage. A lexical set is a set of words (named with a designated element) that share a special characteristic. For example, words belonging to lexical set BATH have the /æ/ phoneme in the United States and /ɑː/ phoneme in Received Pronunciation.
His father was originally from South Africa, and his mother was English; he has two younger brothers. He attended St John's School, Leatherhead, studied languages and taught himself Gregg Shorthand. Having learned Welsh, he was interviewed in Welsh on radio; according to his CV, he has a reasonable knowledge of ten different languages. He was apparently approached by the Home Office to work on speaker identification but turned down the offer as it was still considered unacceptable to be homosexual at the time, and he feared that the security check would make his homosexuality public. In September 2006 he signed a civil partnership with Gabriel Parsons, a native of Montserrat and his partner since 1968.
1962 – ə spesəmin əv britiʃ iŋgliʃ [A specimen of British English]. In: Maître Phonétique Nr. 117, S. 2–5.
1967 – spesimɛn. *dʒəmeikən ˈkriːoul [Specimen. Jamaican Creole]. In: Maître Phonétique, Nr. 127 S. 5.
1968 – Nonprevocalic intrusive r in urban Hampshire. IN: Progress Report, UCL Phonetics Laboratory, S. 56–57
1970 – Local accents in England and Wales. In: J.Ling., Nr. 6, S. 231–252.
1979 – Final voicing and vowel length in Welsh. In: Phonetica'. 36.4–5, S. 344–360.
1980 – The brogue that isn't. In: JIPA vol. 10 (1980), S. 74–79. Can be read on-line.
1985 – English accents in England. In: P. Trudgill (Hrsg.): Language in the British Isles. Cambridge University Press. 55–69.
1985 – English pronunciation and its dictionary representation. In: R. Ilson: (Hrsg.): Dictionaries, lexicography and language learning. Oxford: Pergamon.
1994 – The Cockneyfication of RP?. In: G. Melchers u.a. (Hrsg.): Nonstandard Varieties of Language. Papers from the Stockholm Symposium 11–13 April 1991. 198–205. Stockholm Studies in English LXXXIV. Stockholm: Almqvist & Wiksell International.
1995 – New syllabic consonants in English. In: J. Windsor Lewis (Hrsg.): Studies in General and English Phonetics. Essays in honour of Prof. J.D. O'Connor. London: Routledge. ISBN0-415-08068-1.
1995 – Age grading in English pronunciation preferences. In: Proceedings of ICPhS 95, Stockholm, vol. 3:696–699.
1996 – Why phonetic transcription is important. In: Malsori (Journal of the Phonetic Society of Korea) 31–32, S. 239–242.
1997 – What's happening to Received Pronunciation?. In: English Phonetics (English Phonetic Society of Japan), 1, S. 13–23.
1997 – Our changing pronunciation. In: Transactions of the Yorkshire Dialect Society xix, S. 42–48
1997 – One of three named "main technical authors" for Part IV, Spoken language reference materials. In: D. Gibbon u.a. (Hrsg.): Handbook of Standards and Resources for Spoken Language Systems. Berlin: Mouton de Gruyter, 1997.
1997 – Whatever happened to Received Pronunciation? In: Medina & Soto (Hrsg): II Jornadas de Estudios Ingleses, Universidad de Jaén, Spain, S. 19–28.
1997 – Is RP turning into Cockney?. In: M. P. Dvorzhetska, A. A. Kalita (Hrsg.): Studies in Communicative Phonetics and Foreign Language Teaching Methodology. Kyiv State Linguistic University, Ukraine, S. 10–15.
1999 – Which pronunciation do you prefer?. In: IATEFL Bd. 149, June–July 1999, "The Changing Language", S. 10–11.
1999 – Pronunciation preferences in British English. A new survey. In: Proc. of the 14th International Congress of Phonetic Sciences, San Francisco, 1999.
2000 – British English pronunciation preferences. A changing scene. In: Journal of the International Phonetic Association (1999) 29 (1), S. 33–50.
2000 – Overcoming phonetic interference. In: English Phonetics (Journal of the English Phonetic Society of Japan), Nr. 3, S. 9–21.
2001 – Orthographic diacritics. In: Language Problems and Language Planning 24.3.
2002 – John Wells. In: K. Brown, V. Law (Hrsg.): Linguistics in Britain. Personal histories. Publications of the Philological Society, 36. Oxford: Blackwell.
2002 – Accents in Britain today. In: Ewa Waniek-Klimczak, Patrick J. Melia (Hrsg.): Accents and Speech in Teaching English Phonetics and Phonology. Lang, Frankfurt/M. 2002 . ISBN3-631-39616-3, S. 9–17.
2003 – Phonetic research by written questionnaire. In: M. J. Solé, u.a. (Hrsg.): Proc. 15th Int. Congress of Phonetic Sciences, Barcelona, R.4.7:4
2003 – Phonetic symbols in word processing and on the web. In: M. J. Solé u.a. (Hrsg..): Proc. 15th Int. Congress of Phonetic Sciences, Barcelona, S.2.8:6