List of constructed languages (conlangs) by year and type

A constructed language (conlang) is a language whose sounds, words or grammar were deliberately designed by a person or group instead of growing out of everyday speech. The main types are international auxiliary languages (auxlangs, made for communication between nations, such as Esperanto), artistic languages (artlangs, made for fiction, beauty or play, such as Klingon), and engineered languages (built to test logic, philosophy or linguistic ideas, such as Lojban). Related groups are a priori languages (invented roots) against a posteriori ones (built from existing languages), and zonal languages for one language family, such as Interslavic. The categories overlap. Esperanto is the most widely spoken: published estimates run from about 60,000 to 2 million speakers, and no other conlang has a documented community of more than a few thousand people.

#Table of notable constructed languages

The table is sorted by year of first publication or first use. Speaker numbers are shown only where a published estimate exists; "not known" means no reliable count was found. Estimates of this kind are rough and often disputed. For a detailed comparison of the best-known auxlangs, see Esperanto compared with other constructed languages.

#How many constructed languages exist?

Nobody knows exactly, because many are private projects that are never published. The linguist Carolina González (Cambridge University Press, 2025) writes that more than 1,000 constructed languages have been documented since the 12th century, and the German Wikipedia article on planned languages likewise speaks of over a thousand projects, of which only a few became well known. Louis Couturat and Léopold Leau reviewed 38 international language projects as early as 1903. Counts differ because "constructed language" can include fictional, philosophical and personal languages or only those meant for real use.

#Which constructed languages are used most today?

Esperanto leads by a wide margin. Svend Vendelbo Nielsen estimated about 60,000 speakers in 2017, while Sidney Culbert's survey, repeated in Ethnologue, gives 2 million; see how many people speak Esperanto for every estimate and method. Other figures are much smaller:

• Klingon: the linguist Arika Okrent estimated that 20 or 30 people can carry on a spontaneous conversation, with hundreds who use it in writing (reported by Mental Floss).
• Toki Pona: its creator said in 2007 that at least 100 people spoke it fluently. The 2024 community census had 1,997 respondents, 53% of them at conversation level or above. The Toki Pona site itself claims tens of thousands of speakers in 2025, so estimates differ by two orders of magnitude depending on what is counted.
• Ido: from 100–200 (Detlev Blanke, 2000) to 1,000–5,000 (Ido Foundation).
• Interlingua and Interslavic: Interlingua has a few hundred to about 1,500 users; Interslavic projects claim 7,000–20,000, a figure not independently counted. Sources for these and the other auxlangs are on Esperanto compared with other constructed languages.

#Do any constructed languages have native speakers?

Esperanto does. Its native speakers (denaskuloj) are children who grew up with it at home, usually with Esperanto-speaking parents. Estimates are about 1,000–2,000, and German Wikipedia calls Esperanto the only planned language with native speakers. See native speakers of Esperanto. Klingon and Ithkuil have no documented native speakers.

#Which constructed languages have ISO codes?

ISO 639-3, maintained by SIL International, gives codes to individual languages and classes the ones below as "Constructed". ISO 639-2 also has the collective code art for artificial languages in general.

A code means that the language is documented well enough to be identified, not that it has a large community. Solresol, for example, was reportedly refused a code in 2017 because it is not used in a large and diverse community, according to the language magazine Babbel.

#Why did most auxiliary languages fail?

Most had a single author who kept changing the language, no lasting community, or no practical reason for anyone to learn them. Volapük is the classic case: it grew fast in the 1880s and lost most of its followers within a few years. Esperanto's stability came from a fixed core and a speaker-owned language, as explained on Esperanto compared with other constructed languages. Artlangs and engineered languages, by contrast, were never meant to replace national languages, so "failure" is the wrong measure for them.

#Common questions

#What is the most spoken constructed language?

Esperanto, with an estimated 60,000 to 2 million speakers. No other constructed language has a documented community of that size.

#What is the oldest constructed language?

Hildegard of Bingen's Lingua Ignota, from the 12th century, is usually named as one of the earliest known, though it is mostly a glossary of invented words attached to Latin grammar. The first widely used auxlang was Volapük in 1879–80.

#Are Klingon and Dothraki real languages?

They are real in the sense that they have grammar and vocabulary and people can learn them. They were made for television and film, however, and few people use them outside fandom.

#Is a constructed language the same as a dialect or a pidgin?

No. A dialect or pidgin develops over time among its speakers, while a constructed language is designed deliberately. Lingua Franca Nova is inspired by a pidgin but was designed by one author.

#Which constructed language is the easiest to learn?

It depends on the purpose. Toki Pona has the smallest vocabulary, about 120–137 core words, but it is not designed for precise everyday communication. Among languages meant for full communication, Esperanto has a regular grammar and by far the most learners and learning materials. See what is the easiest language to learn? and how to learn Esperanto.

#Sources

• Wikipedia, Constructed language, International auxiliary language and List of constructed languages
• Wikipedia (de), Plansprache
• Carolina González, Inventing Languages: A Practical Introduction, Cambridge University Press, 2025
• Wikipedia, Lingua Ignota, Solresol, Latino sine flexione, Blissymbols, Ithkuil, Kotava, Láadan, Toki Pona, Na'vi language, Dothraki language
• Babbel, The history of Solresol and The story of Blissymbolics
• Mental Floss, Constructed languages you can learn (Okrent's Klingon estimate; Loglan and Lojban)
• Klingon Language Institute, Klingon history
• Mother Jones, The linguist behind Avatar; WHYY, He brought Game of Thrones languages to life
• Lojban wiki, About Lojban and Logical Language History
• Tolkien Gateway, Qenyaqetsa; Ardalambion, The Qenya Lexicon reviewed
• ithkuil.place, Ithkuil: A Philosophical Design for a Hypothetical Language (2004 mirror)
• Conlang Atlas of Language Structures, Kotava; Le Petit Prince in languages, Kotava
• Jayeless.net, Lingua Franca Nova; Lingclusive, The Elefen in the room
• Omniglot, Slovio; Encyclopaedia Britannica 1911, Volapük (Idiom Neutral and the Volapük Academy)
• Jan van Steenbergen, A short history of Interslavic
• SIL International, ISO 639-3 code pages: epo, vol, ido, ile, nov, ina, jbo, tlh, tok, isv, lfn, avk, qya, sjn, zbl, art
• Libera Folio, "Nova takso: 60.000 parolas Esperanton" (Nielsen, 2017); Ethnologue, Esperanto entry, 16th edition (2009)
• Jan Tamalu and others, Results of the 2024 Toki Pona census; Toki Pona official site
• Ido Foundation, IDO; Detlev Blanke (2000), cited in Sabine Fiedler, Phraseology in planned languages, 2007
• Wikipedia, Volapük, Ido, Interlingue, Novial, Interlingua, Lojban, Klingon language, Interslavic; see also the sources of Esperanto compared with other constructed languages