> ## Documentation Index
> Fetch the complete documentation index at: https://algolia.com/llms.txt
> Use this file to discover all available pages before exploring further.

# queryLanguages

> Languages used to apply language-specific processing such as stop word removal, plural handling, and word detection

export const Setting = ({type, default: defaultValue, defaultNote, scope, min, max, formerly}) => {
  const renderedDefault = defaultValue === '' ? '""' : defaultValue;
  const renderedNote = defaultNote ? `(${defaultNote})` : '';
  return <ul>
      <li><strong>Type:</strong> <code>{type}</code></li>
      <li><strong>Default:</strong> <code>{renderedDefault}</code>{renderedNote}</li>
      {min && <li><strong>Min:</strong> <code>{min}</code></li>}
      {max && <li><strong>Max:</strong> <code>{max}</code></li>}
      <li><strong>Scope:</strong> <a href="/doc/api-reference/api-parameters"><code>{scope}</code></a></li>
      {formerly && <li>
          <strong>Deprecated name:</strong> <code>{formerly}</code>
        </li>}
    </ul>;
};

<Setting type="list<enum<string>>" default="[]" scope="settings,search" formerly="expectedLanguages" />

The `queryLanguages` parameter defines the languages used for **language-specific search behavior**,
including:

* Stop word removal with [`removeStopWords`](/doc/api-reference/api-parameters/removeStopWords)
* Plural and inflection normalization with [`ignorePlurals`](/doc/api-reference/api-parameters/ignorePlurals)
* Word segmentation and tokenization for CJK languages (Chinese, Japanese, Korean)

## Usage

* If `queryLanguages` isn't set, Algolia falls back to:

  * The languages defined in `ignorePlurals` or `removeStopWords`
  * All [supported languages](/doc/guides/managing-results/optimize-search-results/handling-natural-languages-nlp/in-depth/supported-languages) if none are specified

* For **CJK support**, the first language in the list must be `"zh"`, `"ja"`, or `"ko"`.
  This ensures correct dictionary-based segmentation.

* Only include languages that are present in your content to avoid unexpected behavior.

* To support Japanese, you must also set `"ja"` in [`indexLanguages`](/doc/api-reference/api-parameters/indexLanguages).

* This setting defines the default behavior for other parameters.
  You can override this default per setting—for example, apply plural handling in English but stop word removal in French.

For a list of supported language codes,
see [Supported languages](/doc/guides/managing-results/optimize-search-results/handling-natural-languages-nlp/in-depth/supported-languages).

## Example

<AccordionGroup>
  <Accordion title="Current API clients" defaultOpen="true">
    <CodeGroup>
      ```csharp C# theme={"system"}
      var response = await client.SetSettingsAsync(
        "ALGOLIA_INDEX_NAME",
        new IndexSettings
        {
          QueryLanguages = new List<SupportedLanguage> { Enum.Parse<SupportedLanguage>("Es") },
          RemoveStopWords = new RemoveStopWords(true),
          IgnorePlurals = new IgnorePlurals(true),
        }
      );
      ```

      ```dart Dart theme={"system"}
      final response = await client.setSettings(
        indexName: "ALGOLIA_INDEX_NAME",
        indexSettings: IndexSettings(
          queryLanguages: [
            SupportedLanguage.fromJson("es"),
          ],
          removeStopWords: true,
          ignorePlurals: true,
        ),
      );
      ```

      ```go Go theme={"system"}
      response, err := client.SetSettings(client.NewApiSetSettingsRequest(
        "ALGOLIA_INDEX_NAME",
        search.NewEmptyIndexSettings().SetQueryLanguages(
          []search.SupportedLanguage{search.SupportedLanguage("es")}).SetRemoveStopWords(search.BoolAsRemoveStopWords(true)).SetIgnorePlurals(search.BoolAsIgnorePlurals(true))))
      if err != nil {
        // handle the eventual error
        panic(err)
      }
      ```

      ```java Java theme={"system"}
      client.setSettings(
        "ALGOLIA_INDEX_NAME",
        new IndexSettings()
          .setQueryLanguages(Arrays.asList(SupportedLanguage.ES))
          .setRemoveStopWords(RemoveStopWords.of(true))
          .setIgnorePlurals(IgnorePlurals.of(true))
      );
      ```

      ```javascript JavaScript theme={"system"}
      const response = await client.setSettings({
        indexName: 'theIndexName',
        indexSettings: { queryLanguages: ['es'], removeStopWords: true, ignorePlurals: true },
      });
      ```

      ```kotlin Kotlin theme={"system"}
      var response = client.setSettings(
        indexName = "ALGOLIA_INDEX_NAME",
        indexSettings = IndexSettings(
          queryLanguages = listOf(SupportedLanguage.entries.first { it.value == "es" }),
          removeStopWords = RemoveStopWords.of(true),
          ignorePlurals = IgnorePlurals.of(true),
        ),
      )
      ```

      ```php PHP theme={"system"}
      $response = $client->setSettings(
          'ALGOLIA_INDEX_NAME',
          ['queryLanguages' => [
              'es',
          ],
              'removeStopWords' => true,
              'ignorePlurals' => true,
          ],
      );
      ```

      ```python Python theme={"system"}
      response = client.set_settings(
          index_name="ALGOLIA_INDEX_NAME",
          index_settings={
              "queryLanguages": [
                  "es",
              ],
              "removeStopWords": True,
              "ignorePlurals": True,
          },
      )
      ```

      ```ruby Ruby theme={"system"}
      response = client.set_settings(
        "ALGOLIA_INDEX_NAME",
        Algolia::Search::IndexSettings.new(query_languages: ["es"], remove_stop_words: true, ignore_plurals: true)
      )
      ```

      ```scala Scala theme={"system"}
      val response = Await.result(
        client.setSettings(
          indexName = "ALGOLIA_INDEX_NAME",
          indexSettings = IndexSettings(
            queryLanguages = Some(Seq(SupportedLanguage.withName("es"))),
            removeStopWords = Some(RemoveStopWords(true)),
            ignorePlurals = Some(IgnorePlurals(true))
          )
        ),
        Duration(100, "sec")
      )
      ```

      ```swift Swift theme={"system"}
      let response = try await client.setSettings(
          indexName: "ALGOLIA_INDEX_NAME",
          indexSettings: IndexSettings(
              ignorePlurals: SearchIgnorePlurals.bool(true),
              removeStopWords: SearchRemoveStopWords.bool(true),
              queryLanguages: [SearchSupportedLanguage.es]
          )
      )
      ```
    </CodeGroup>
  </Accordion>

  <Accordion title="Legacy API clients">
    <CodeGroup>
      ```cs C# theme={"system"}
      IndexSettings settings = new IndexSettings();
      settings.QueryLanguages = new List { "es" };
      settings.RemoveStopWords = true;
      settings.IgnorePlurals = true;

      index.SetSettings(settings);
      ```

      ```go Go theme={"system"}
      res, err := index.SetSettings(search.Settings{
      	QueryLanguages:  opt.QueryLanguages("es"),
      	RemoveStopWords: opt.RemoveStopWords(true),
      	IgnorePlurals:   opt.IgnorePlurals(true),
      })
      ```

      ```java Java theme={"system"}
      index.setSettings(
              new IndexSettings()
                      .setQueryLanguages(Collections.singletonList("es"))
                      .setRemoveStopWords(RemoveStopWords.of(true))
                      .setIgnorePlurals(IgnorePlurals.of(true))
      );
      ```

      ```js JavaScript theme={"system"}
      index
        .setSettings({
          queryLanguages: ["es"],
          removeStopWords: true,
          ignorePlurals: true,
        })
        .then(() => {
          // done
        });
      ```

      ```kotlin Kotlin theme={"system"}
      val settings = settings {
          queryLanguages {
              +Spanish
          }
          ignorePlurals = IgnorePlurals.True
          removeStopWords = RemoveStopWords.True
      }

      index.setSettings(settings)
      ```

      ```php PHP theme={"system"}
      $index->setSettings([
        'queryLanguages' => ['es'],
        'removeStopWords' => true,
        'ignorePlurals' => true
      ]);
      ```

      ```python Python theme={"system"}
      index.set_settings(
          {"queryLanguages": ["es"], "removeStopWords": True, "ignorePlurals": True}
      )
      ```

      ```ruby Ruby theme={"system"}
      index.set_settings(
        {
          queryLanguages: ["es"],
          removeStopWords: true,
          ignorePlurals: true
        }
      )
      ```

      ```scala Scala theme={"system"}
      client.execute {
        setSettings of "myIndex" `with` IndexSettings(
          queryLanguages = Some(QueryLanguages.list(Seq("es")),
          removeStopWords = Some(RemoveStopWords.`true`),
          ignorePlurals = Some(IgnorePlurals.`true`)
        )
      }
      ```

      ```swift Swift theme={"system"}
      let settings = Settings()
        .set(\.queryLanguages, to: [.spanish])
        .set(\.ignorePlurals, to: true)
        .set(\.removeStopWords, to: true)

      index.setSettings(settings) { result in
        if case .success(let response) = result {
          print("Response: \(response)")
        }
      }
      ```
    </CodeGroup>
  </Accordion>
</AccordionGroup>