Classify text

Analyze text and return a list of content categories that apply to the text.

Code sample


        private static void ClassifyTextFromText(string text)
            var client = LanguageServiceClient.Create();
            var response = client.ClassifyText(new Document()
                Content = text,
                Type = Document.Types.Type.PlainText

        private static void WriteCategories(IEnumerable<ClassificationCategory> categories)
            foreach (var category in categories)
                Console.WriteLine($"\tCategory: {category.Name}");
                Console.WriteLine($"\t\tConfidence: {category.Confidence}");


func classifyText(ctx context.Context, client *language.Client, text string) (*languagepb.ClassifyTextResponse, error) {
	return client.ClassifyText(ctx, &languagepb.ClassifyTextRequest{
		Document: &languagepb.Document{
			Source: &languagepb.Document_Content{
				Content: text,
			Type: languagepb.Document_PLAIN_TEXT,


// Instantiate the Language client
try (LanguageServiceClient language = LanguageServiceClient.create()) {
  // set content to the text string
  Document doc = Document.newBuilder().setContent(text).setType(Type.PLAIN_TEXT).build();
  ClassifyTextRequest request = ClassifyTextRequest.newBuilder().setDocument(doc).build();
  // detect categories in the given text
  ClassifyTextResponse response = language.classifyText(request);

  for (ClassificationCategory category : response.getCategoriesList()) {
        "Category name : %s, Confidence : %.3f\n",
        category.getName(), category.getConfidence());


// Imports the Google Cloud client library
const language = require('@google-cloud/language');

// Creates a client
const client = new language.LanguageServiceClient();

 * TODO(developer): Uncomment the following line to run this code.
// const text = 'Your text to analyze, e.g. Hello, world!';

// Prepares a document, representing the provided text
const document = {
  content: text,
  type: 'PLAIN_TEXT',

// Classifies text in the document
const [classification] = await client.classifyText({document});
classification.categories.forEach(category => {
  console.log(`Name: ${}, Confidence: ${category.confidence}`);


use Google\Cloud\Language\V1\Document;
use Google\Cloud\Language\V1\Document\Type;
use Google\Cloud\Language\V1\LanguageServiceClient;

/** Uncomment and populate these variables in your code */
// $text = 'The text to analyze.';

// Make sure we have enough words (20+) to call classifyText
if (str_word_count($text) < 20) {
    printf('20+ words are required to classify text.' . PHP_EOL);
$languageServiceClient = new LanguageServiceClient();
try {
    // Create a new Document, add text as content and set type to PLAIN_TEXT
    $document = (new Document())

    // Call the analyzeSentiment function
    $response = $languageServiceClient->classifyText($document);
    $categories = $response->getCategories();
    // Print document information
    foreach ($categories as $category) {
        printf('Category Name: %s' . PHP_EOL, $category->getName());
        printf('Confidence: %s' . PHP_EOL, $category->getConfidence());
} finally {


from import language_v1

def sample_classify_text(text_content):
    Classifying Content in a String

      text_content The text content to analyze. Must include at least 20 words.

    client = language_v1.LanguageServiceClient()

    # text_content = 'That actor on TV makes movies in Hollywood and also stars in a variety of popular new TV shows.'

    # Available types: PLAIN_TEXT, HTML
    type_ = language_v1.Document.Type.PLAIN_TEXT

    # Optional. If not specified, the language is automatically detected.
    # For list of supported languages:
    language = "en"
    document = {"content": text_content, "type_": type_, "language": language}

    response = client.classify_text(request = {'document': document})
    # Loop through classified categories returned from the API
    for category in response.categories:
        # Get the name of the category representing the document.
        # See the predefined taxonomy of categories:
        print(u"Category name: {}".format(
        # Get the confidence. Number representing how certain the classifier
        # is that this category represents the provided text.
        print(u"Confidence: {}".format(category.confidence))


# text_content = "Text to classify"

require "google/cloud/language"

language = Google::Cloud::Language.language_service

document = { content: text_content, type: :PLAIN_TEXT }
response = language.classify_text document: document

categories = response.categories

categories.each do |category|
  puts "Name: #{} Confidence: #{category.confidence}"

What's next

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