Text Normalization - KugelAudio

Text normalization converts numbers, dates, times, and other non-verbal text into spoken words (for example “3 apples” becomes “three apples”). How it works, the supported languages and their codes are documented in Text processing. The JavaScript SDK controls it with the normalize and language options:

// With explicit language (recommended)
const audio = await client.tts.generate({
  text: 'I bought 3 items for €50.99 on 01/15/2024.',
  voiceId: 1071,
  normalize: true,
  language: 'en',
});

// Without language: normalized in the voice's primary language (English if none)
const voiceLanguageAudio = await client.tts.generate({
  text: 'Ich habe 3 Artikel für 50,99€ gekauft.',
  voiceId: 1071,
  normalize: true,
  // language not specified: the voice's primary language is used
});

Using normalize: true without specifying language may cause incorrect normalizations, especially for short texts or languages that share similar vocabulary. Always specify language when you know it.

Spell Tags

Wrap text in <spell> tags to have it read character by character (emails, codes, acronyms). Tag semantics and per-language character names are in Spell tags. In a streaming session, a tag split across tokens is handled for you:

const session = client.tts.streamingSession(
  { voiceId: 1071, normalize: true, language: 'en' },
  { onChunk: (chunk) => playAudio(chunk.audio) },
);
await session.connect();

session.send('My code is <spell>');
session.send('ABC123</spell>');

await session.close();

playAudio stands for your own playback function.

Next steps

Dictionaries: per-project pronunciation and replacement lists
Generate Speech: generation parameters including normalize and language

Last modified on September 22, 2026