Supported languages for indexing features

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Important
Language support and relevance disclaimer

The Coveo Platform supports a wide range of languages across indexing, machine learning models, and user interfaces; however, the depth of linguistic processing varies by language. Support for a language doesn’t constitute a commitment to equivalent relevance, accuracy, or feature parity.

For example, queries and indexed content in languages such as English, French, German, and Spanish achieve higher and more consistent relevance due to more comprehensive language analysis and optimized platform components. Conversely, for other languages that are technically supported but for which the platform isn’t fully optimized, search relevance, generated answers, and overall accuracy can be reduced or be less consistent. Accordingly, language support doesn’t guarantee equal relevance quality, and observed outcomes can vary depending on the language.

The table below lists the 58 languages Coveo supports where encoding, excerpt, language detection, and thesaurus features are available for indexing. Coveo can also index content in languages other than those listed below as long as:

  • The language uses spaces to separate words.

  • The item encodes characters in Unicode.

For languages meeting these requirements, most language features are supported except language detection, decompounding, and stemming.

Note

Since result ranking is partly based on summarization and key-concept extraction techniques, English, French, German, and Spanish queries return the most relevant results consistently.
Language Locale Encoding, excerpt, and thesaurus Did you mean Language detection Stemming Decompounding

English[1]

en

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N/A

French[1]

fr

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N/A

German[1]

de

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Spanish[1]

es

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N/A

Danish

da

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check

Dutch

nl

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check

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Finnish

fi

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check

check

Hungarian

hu

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N/A

Italian

it

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N/A

Norwegian

no

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check

check

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check

Portuguese

pt

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N/A

Swedish

sv

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check

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check

Turkish

tr

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N/A

Catalan

ca

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N/A

Romanian

ro

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N/A

Valencian

ca

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N/A

Armenian

hy

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N/A

Russian

ru

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N/A

Chinese (traditional and simplified)[2],[3]

zh

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x

N/A

Greek

el

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N/A

Hindi

hi

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N/A

Japanese[2],[3]

ja

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x

N/A

Korean[2],[3]

ko

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x

N/A

Thai

th

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x

N/A

Arabic

ar

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N/A

Basque

eu

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x

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N/A

Lithuanian

lt

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N/A

Czech

cs

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N/A

Indonesian

id

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N/A

Polish

pl

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N/A

Albanian

sq

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x

N/A

Afrikaans

af

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x

N/A

Belarusian

be

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x

N/A

Bulgarian

bg

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N/A

Burmese

my

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x

N/A

Croatian

hr

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N/A

Esperanto

eo

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x

N/A

Estonian

et

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N/A

Filipino

fil

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x

x

N/A

Hebrew

he

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x

N/A

Icelandic

is

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x

N/A

Kazakh

kk

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x

N/A

Latvian

lv

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x

N/A

Macedonian

mk

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x

N/A

Malay

ms

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x

x

N/A

Moldovan

ro

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check

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N/A

Mongolian

mn

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x

x

N/A

Norwegian Bokmål[4]

nb

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x

check

check

Persian

fa

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x

N/A

Serbian

sr

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N/A

Slovak

sk

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N/A

Slovenian

sl

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N/A

Swahili

sw

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x

N/A

Tagalog

tl

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x

N/A

Ukrainian

uk

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x

N/A

Uzbek

uz

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x

N/A

Vietnamese

vi

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x

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x

N/A

Yiddish

yi

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x

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N/A

2. Wildcards in queries are not supported.

1. The index can also generate item summaries.

3. A specialized tokenizer based on dictionaries is used to split CJK characters into words, which can impact search results relevancy.

4. Will be detected as Norwegian (no).

Troubleshooting language indexing issues

Note

Context and symptoms

You see inconsistent results when searching in a specific language on your website.

Cause

  • Most languages are limited to the Snowball stemming algorithms. Some rules are incomplete, meaning variations of words aren’t always stemmed correctly.

    For example, when searching in German, the words passieren, passierend, and passiert might result in different stems, while passieren and passiere share the same stem.

  • The correct language isn’t being detected. Stemming is only applied if the language is detected for both the query and the indexed documents.

Resolution