> ## Documentation Index > Fetch the complete documentation index at: https://docs.deepdub.ai/llms.txt > Use this file to discover all available pages before exploring further. # Generate and stream TTS audio > Generate and stream TTS audio based on the provided text. Returns an audio stream in the specified format (default MP3). Supported formats: `mp3`, `opus`, `mulaw`. For `wav` or `s16le` output, use the WebSocket API. ## Supported languages | Language | Locale code | | ------------------------ | ----------- | | Arabic (Lebanon) | `ar-LB` | | Arabic (Qatar) | `ar-QA` | | Arabic (Saudi) | `ar-SA` | | Arabic (Standard) | `ar-SA` | | Arabic (Syrian) | `ar-SY` | | Czech (Standard) | `cs-CZ` | | Danish (Standard) | `da-DK` | | Dutch (Netherlands) | `nl-NL` | | English (Generic) | `en-GB` | | English (Standard) | `en-AU` | | English (United States) | `en-US` | | Estonian (Standard) | `et-EE` | | Finnish (Standard) | `fi-FI` | | French (Standard) | `fr-FR` | | German (Standard) | `de-DE` | | Greek (Standard) | `el-GR` | | Hebrew (Standard) | `he-IL` | | Hindi (Standard) | `hi-IN` | | Hungarian (Standard) | `hu-HU` | | Indonesian (Standard) | `id-ID` | | Italian (Standard) | `it-IT` | | Japanese (Standard) | `ja-JP` | | Korean (Standard) | `ko-KR` | | Macedonian (Standard) | `mk-MK` | | Norwegian (Standard) | `nb-NO` | | Polish (Standard) | `pl-PL` | | Portuguese (Brazil) | `pt-BR` | | Romanian (Standard) | `ro-RO` | | Russian (Standard) | `ru-RU` | | Spanish (Latam) | `es-419` | | Spanish (Latam — Mexico) | `es-MX` | | Spanish (Standard) | `es-ES` | | Swedish (Standard) | `sv-SE` | | Tamil (Standard) | `ta-IN` | | Thai (Standard) | `th-TH` | | Turkish (Standard) | `tr-TR` | ## Supported output formats The REST API streams audio as raw bytes in the HTTP response body. Supported formats: | Format | Description | | ------- | ----------------------------------------------------------------------------------------------------- | | `mp3` | Compressed audio, smallest file size. **Default.** | | `opus` | High-quality compressed audio, efficient for streaming. | | `mulaw` | 8-bit µ-law encoding, commonly used in telephony. Defaults to 8000 Hz if no sample rate is specified. | The REST API supports `mp3`, `opus`, and `mulaw` only. For `wav` or `s16le` output, use the [WebSocket API](/api-reference/websocket/overview). ## Sample rates The sample rate is passed through to the audio conversion layer. The internal generation runs at 48 kHz and is resampled to the requested rate. If no sample rate is specified, `mulaw` defaults to 8000 Hz. ### REST vs WebSocket comparison | Feature | REST API | WebSocket API | | --------------------------------- | --------------------------------------------- | --------------------------------------------------------------------- | | **Delivery** | Streaming HTTP response (chunked audio bytes) | Chunked audio delivered incrementally as base64-encoded JSON messages | | **Formats** | `mp3`, `opus`, `mulaw` | `wav` (default), `mp3`, `opus`, `mulaw`, `s16le` | | **Streaming input (ctx/isFinal)** | Not supported | `wav`, `s16le`, `mulaw` only | | **Default format** | `mp3` | `wav` | | **Default mulaw sample rate** | 8000 Hz | 8000 Hz | | **Best for** | Simple integrations, file generation | Real-time playback, low-latency applications | ## OpenAPI ````yaml post /tts openapi: 3.0.0 info: title: Deepdub API description: >- Deepdub's Text-to-Speech API enables high-quality, expressive speech generation with voice cloning, accent control, and real-time streaming capabilities. contact: email: support@deepdub.ai version: '1.0' servers: - url: https://restapi.deepdub.ai/api/v1 description: Production security: - ApiKeyAuth: [] externalDocs: description: OpenAPI url: https://restapi.deepdub.ai/api/v1/swagger/index.html paths: /tts: post: tags: - TTS summary: Generate and stream TTS audio description: >- Generate and stream TTS audio based on the provided text. Returns an audio stream in the specified format (default MP3). Supported formats: `mp3`, `opus`, `mulaw`. For `wav` or `s16le` output, use the WebSocket API. operationId: generateTTS parameters: - description: API Key name: x-api-key in: header required: true schema: type: string default: dd-00000000000000000000000065c9cbfe example: dd-00000000000000000000000065c9cbfe requestBody: required: true content: application/json: schema: $ref: '#/components/schemas/model.GenerationRequest' example: model: dd-etts-3.0 targetText: Hello world, welcome to Deepdub. locale: en-US voicePromptId: bd1b00bb-be1c-4679-8eaa-0fcbfd4ff773 responses: '200': description: >- Audio stream in the requested format (MP3, Opus, or mulaw depending on `format` parameter). The response body is raw audio bytes. '400': description: Bad request — invalid or missing parameters content: application/json: schema: $ref: '#/components/schemas/model.APIError' example: success: false message: 'Invalid request: missing required field ''targetText''' '401': description: Unauthorized — invalid or missing API key content: application/json: schema: $ref: '#/components/schemas/model.APIError' example: success: false message: 'Unauthorized: invalid or missing API key' '402': description: Insufficient credits — your account has run out of TTS credits content: application/json: schema: $ref: '#/components/schemas/model.APIError' example: success: false message: 'InsufficientCredits: your account has no remaining credits' '429': description: Rate limit exceeded — too many concurrent requests content: application/json: schema: $ref: '#/components/schemas/model.APIError' example: success: false message: 'RateLimit: concurrent request limit exceeded' '500': description: Internal server error content: application/json: schema: $ref: '#/components/schemas/model.APIError' example: success: false message: Internal server error components: schemas: model.GenerationRequest: description: >- Request structure for TTS generation endpoints. **Optional parameters** (not shown in playground): `generationId` (string), `targetDuration` (number, seconds), `tempo` (number, 0.5–2.0), `variance` (number, 0.0–1.0), `seed` (integer), `temperature` (number, 0.0–1.0), `sampleRate` (integer), `format` (string: mp3/opus/mulaw — default mp3), `promptBoost` (boolean), `superStretch` (boolean), `realtime` (boolean), `cleanAudio` (boolean, default true), `autoGain` (boolean), `publish` (boolean), `accentControl` (object with accentBaseLocale, accentLocale, accentRatio), `performanceReferencePromptId` (string), `voiceReference` (string, base64-encoded audio). type: object required: - locale - model - targetText - voicePromptId properties: model: description: Model ID to use for generation type: string default: dd-etts-3.0 example: dd-etts-3.0 targetText: description: Text to be converted to speech type: string example: Hello world, welcome to Deepdub. locale: description: Language locale code (e.g., en-US, fr-FR) type: string example: en-US voicePromptId: description: ID of the voice prompt to use for generation type: string example: bd1b00bb-be1c-4679-8eaa-0fcbfd4ff773 additionalProperties: true model.APIError: description: Error response returned for all non-2xx status codes type: object required: - success - message properties: success: description: Always false for error responses type: boolean example: false message: description: Human-readable error message type: string example: Invalid request parameters securitySchemes: ApiKeyAuth: type: apiKey in: header name: x-api-key description: API key for authentication. Must start with `dd-` prefix. ````