> ## Documentation Index > Fetch the complete documentation index at: https://apidocs.erlcrussia.com/llms.txt > Use this file to discover all available pages before exploring further. # Text to speech > Converts text into an audio file. Requires an AI key with the voice scope. ## OpenAPI ````yaml en/openapi/en-openai-api-openapi.yaml POST /v1/audio/speech openapi: 3.1.0 info: title: ER:LC Russia - OpenAI-Compatible API version: 1.0.0 description: >- OpenAI-compatible Chat Completions, model listing and retrieval, and speech methods for ER:LC Russia. See each method for its supported parameters. servers: - url: https://api.erlcrussia.com description: Main server - url: https://api.erlcrussia.xyz description: Backup server security: [] tags: - name: Audio - name: Chat Completions - name: Models paths: /v1/audio/speech: post: tags: - Audio summary: Text to speech description: >- Converts text into an audio file. Requires an AI key with the voice scope. requestBody: required: true content: application/json: schema: type: object required: - input properties: model: type: string enum: - emmy-voice-1 - supertonic - tts-1 - tts-1-hd default: emmy-voice-1 input: type: string minLength: 1 maxLength: 6000 description: Текст для озвучивания. language: type: string enum: - ru - uk - be - en - es - it - fr - zh - ja - ko default: ru voice: type: string enum: - default - F1 - F2 - emmy - emmy-v2 - alloy - nova default: default response_format: type: string enum: - mp3 - wav - pcm - aac - flac - opus default: mp3 speed: type: number minimum: 0.25 maximum: 4 default: 1 stream: type: boolean default: false description: >- ER:LC Russia extension: an NDJSON stream with one line per sentence. Use `stream_format: sse` for the OpenAI format. stream_format: type: string enum: - audio - sse default: audio description: >- `audio` returns the whole file (default), `sse` streams `speech.audio.delta` and `speech.audio.done` events. example: model: emmy-voice-1 input: Привет! Чем я могу помочь? language: ru voice: F1 response_format: mp3 speed: 1 responses: '200': description: Successful response. content: audio/mpeg: schema: type: string format: binary application/octet-stream: schema: type: string format: binary application/x-ndjson: schema: type: string text/event-stream: schema: type: string description: >- Event stream for `stream_format: sse`: `speech.audio.delta` with base64 audio and `speech.audio.done` with `usage`. example: >+ data: {"type":"speech.audio.delta","audio":"SUQzBAAAAAAA..."} data: {"type":"speech.audio.done","usage":{"input_tokens":7,"output_tokens":0,"total_tokens":7}} headers: x-request-id: $ref: '#/components/headers/RequestId' openai-processing-ms: $ref: '#/components/headers/ProcessingMs' x-ratelimit-limit-requests: $ref: '#/components/headers/RateLimitRequests' x-ratelimit-remaining-requests: $ref: '#/components/headers/RateLimitRemainingRequests' x-ratelimit-reset-requests: $ref: '#/components/headers/RateLimitResetRequests' '400': description: Invalid request body. content: application/json: schema: $ref: '#/components/schemas/ErrorResponse' example: error: message: >- We could not parse the JSON body of your request. Make sure it is valid JSON. type: invalid_request_error param: null code: null erlc_code: '5034' '401': description: The key is missing or invalid. content: application/json: schema: $ref: '#/components/schemas/ErrorResponse' example: error: message: >- Incorrect API key provided. Check the key or create a new one in the dashboard. type: invalid_request_error param: null code: invalid_api_key erlc_code: '5008' '429': description: >- Rate limit exceeded (`type: requests`) or AI credits ran out (`type: insufficient_quota`). content: application/json: schema: $ref: '#/components/schemas/ErrorResponse' examples: rate_limit: value: error: message: Rate limit reached. Please slow down and retry later. type: requests param: null code: rate_limit_exceeded erlc_code: '5016' insufficient_quota: value: error: message: >- You exceeded your current quota, please check your plan and billing details. type: insufficient_quota param: null code: insufficient_quota erlc_code: '5038' '503': description: The service is temporarily unavailable. content: application/json: schema: $ref: '#/components/schemas/ErrorResponse' example: error: message: Speech synthesis unavailable type: server_error param: null code: null security: - BearerAuth: [] - ApiKeyAuth: [] components: headers: RequestId: description: Request ID for support. schema: type: string example: req_8f2c1e9b4a7d4c0e9f1a2b3c4d5e6f70 ProcessingMs: description: Request processing time in milliseconds. schema: type: integer example: 412 RateLimitRequests: description: Request limit in the current window. schema: type: integer example: 120 RateLimitRemainingRequests: description: Requests left in the current window. schema: type: integer example: 119 RateLimitResetRequests: description: Time until the limit resets, for example `1s` or `6m0s`. schema: type: string example: 1s schemas: ErrorResponse: type: object description: >- An OpenAI-format error. `code` is an OpenAI string code (`invalid_api_key`, `model_not_found`, `insufficient_quota`, `rate_limit_exceeded`) or `null`. The numeric ER:LC Russia code is in `erlc_code`, see [error codes](/en/documentation/error-codes). properties: error: type: object properties: message: type: string example: Insufficient AI Credits type: type: string enum: - invalid_request_error - insufficient_quota - requests - server_error example: insufficient_quota param: type: - string - 'null' example: null code: type: - string - 'null' example: insufficient_quota erlc_code: type: string description: ER:LC Russia numeric error code. example: '5038' securitySchemes: BearerAuth: type: http scheme: bearer bearerFormat: JWT description: >- Passing the authorization token in the Authorization header: Bearer . ApiKeyAuth: type: apiKey in: header name: erlcrussia-api-ai-key description: The key in the erlcrussia-api-ai-key header. ```` This documentation is built and hosted on [Mintlify](https://mintlify.com), a developer documentation platform.