Detect language API

detect_language takes a text and returns a list of the most likely languages.

It is built on top of the open-source Compact Language Detector 2 (CLD2) library.

Command name: detect_language Success status: 200 OK

On this page

• Common parameters

• Parameters

• Behavior notes

• Response schema

• Request examples

• Errors

Related: Overview, Supported languages, Why WProofreader auto detect language doesn't work for small piece of texts?

Common parameters

cmd selects the command to run.

Name	Type	Required	Description
cmd	string	Yes	Must be detect_language.

These parameters work with any cmd.

Name	Type	Required	Description
serviceid	string	Cloud only	Cloud API key. Required for Cloud requests. Not used on-premises.
format	string	No	Response format. Supported: json (default), xml.
callback	string	No	JSONP wrapper function name. Use only with format=json.

See Overview for details.

Parameters

These are parameters specific to cmd=detect_language.

detect_language does not support short_answer.

Name	Type	Required	Description
text	string	Yes	Text to detect the language for.
locale	string	No	Localization for LangName. Accepted formats: es, es-ES, es_ES.

Behavior notes

• locale affects only LangName. It does not affect detection.

• If the language cannot be detected, you still get 200 OK.

  • The response contains a single item with LangShortCode=Unknown.

• For better accuracy on long texts, split content into sentences.

  • Run detect_language per sentence.

• At least 3 words in text is needed to detected the language. See the information here.

Response schema

The response contains language candidates.

Use format to switch between JSON and XML.

JSON

[
  {
    "LangShortCode": "en_US",
    "LangName": "English (US)",
    "Proportion": 0.98
  }
]

XML

• LangShortCode (string) Detected language code. See Supported languages. Can also be Unknown.

• LangName (string) Human-readable language name. Localized using locale when provided.

• Proportion (number) Confidence / proportion of this language in the text. Higher means “more likely”.

Request examples

Example: single language detected

Request:

GET

GET https://endpoint/api?cmd=detect_language&text=this%20sampl%20text%20demonstrates%20the%20work%20of%20the%20Web%20API%20service.

POST

Response (200 OK):

JSON

[
  {
    "LangShortCode": "en_US",
    "LangName": "English (US)",
    "Proportion": 0.98
  }
]

XML

Example: localized language name (locale=es-ES)

Request:

GET

GET https://endpoint/api?cmd=detect_language&locale=es-ES&text=this%20sampl%20text%20demonstrates%20the%20work%20of%20the%20Web%20API%20service.

POST

Response (200 OK):

JSON

[
  {
    "LangShortCode": "en_US",
    "LangName": "Inglés (Estados Unidos)",
    "Proportion": 0.98
  }
]

XML

Example: no language detected

Request:

GET

GET https://endpoint/api?cmd=detect_language&text=asdfghjkl

POST

Response (200 OK):

JSON (default)

[
  {
    "LangShortCode": "Unknown",
    "LangName": "Unknown",
    "Proportion": 0.0
  }
]

XML

Errors

This command has no command-specific 4xx errors.

When language detection fails, the response is still 200 OK with LangShortCode=Unknown.

Common API errors (for example an invalid serviceid) use the shared error format from Overview.