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

# Spoken Terms Requirements

> Size limits and content rules for Spoken Terms collections and term lists.

## Size limits

| Item                     | Limit                                                    |
| :----------------------- | :------------------------------------------------------- |
| Characters per term list | 300 total                                                |
| Collection name          | 1024 UTF-8 bytes                                         |
| Collections per account  | Limited by your [plan](https://www.deepl.com/en/pro#api) |

Names using only ASCII characters can be up to 1024 characters long; names with multi-byte characters hold fewer.

## Content rules

* Terms are case-sensitive
* Duplicate terms within a list are not allowed (comparison is case-sensitive)
* Terms must not be empty
* Terms must not contain C0 or C1 control characters (including tabs `\t` or newlines `\n` within a term)
* Terms must not contain leading or trailing whitespace

## Availability

Spoken Terms are available on all plans that include the DeepL Voice API, for all [DeepL Voice languages](https://support.deepl.com/hc/en-us/articles/26625846174364-DeepL-Voice-languages). To check a language programmatically, call [`GET /v3/languages?resource=voice`](/api-reference/languages/retrieve-languages-by-resource) and look for the `spoken_terms` feature key on the source language.