# ElevenLabs v4 Text-to-Speech — Atlas Cloud API > ElevenLabs' fastest and most emotive voice model: expressive speech in 90+ languages, with inline delivery tags such as [cheerfully] and [whispers], and multi-speaker dialogue in a single request. This is the machine-readable API reference for **ElevenLabs v4 Text-to-Speech** on Atlas Cloud, a unified API platform for 400+ AI models across text, image, video, audio and 3D. - **Model ID**: `elevenlabs/v4/text-to-speech` - **Built by**: ELEVENLABS - **Modality**: Audio - **Model page**: https://www.atlascloud.ai/models/elevenlabs/v4/text-to-speech - **API key**: https://www.atlascloud.ai/console/api-keys - **Docs**: https://www.atlascloud.ai/docs ## Pricing on Atlas Cloud - $0.08 per 1K characters - Pay-as-you-go. No minimum spend, no subscription required. > **These are the authoritative Atlas Cloud rates for this model.** Any price that > appears in the vendor description further down refers to a different platform or > a different model variant and does not apply here. ## Use this model from an AI agent Atlas Cloud ships three first-party integration surfaces. All three authenticate with the same API key via the `ATLASCLOUD_API_KEY` environment variable. ### MCP server The official MCP server (`atlascloud-mcp`) exposes this model to any MCP-compatible host — Claude Code, OpenAI Codex, Cursor, Gemini CLI, Goose, Claude Desktop. One-line install: ```bash # Claude Code claude mcp add atlascloud -- npx -y atlascloud-mcp # OpenAI Codex CLI codex mcp add atlascloud -- npx -y atlascloud-mcp # Gemini CLI gemini mcp add atlascloud -- npx -y atlascloud-mcp export ATLASCLOUD_API_KEY="your-api-key" ``` Then ask in plain English; the agent calls `atlas_generate_audio` with `model: "elevenlabs/v4/text-to-speech"`. The server fetches each model's schema and validates parameters before submitting, so invalid requests fail fast without spending credits. MCP docs: https://www.atlascloud.ai/docs/mcp-server ### Agent Skills `atlas-cloud-skills` is a portable skill package (API reference, code templates in Python / Node.js / cURL, model IDs with pricing) for Claude Code, Cursor, Codex and 12+ other agents: ```bash npx skills add AtlasCloudAI/atlas-cloud-skills export ATLASCLOUD_API_KEY="your-api-key" ``` Skills docs: https://www.atlascloud.ai/docs/skills ### CLI The `atlas` binary runs Atlas Cloud from a terminal or CI script. Async media jobs are polled and downloaded automatically (use `--no-download` when a script only needs the output URLs): ```bash # Install (Homebrew, npm, or shell installer) brew install AtlasCloudAI/tap/atlascloud # npm install -g atlascloud-cli # curl -fsSL https://raw.githubusercontent.com/AtlasCloudAI/cli/main/install.sh | sh atlas auth login atlas models get elevenlabs/v4/text-to-speech --json ``` CLI docs: https://www.atlascloud.ai/docs/cli ## HTTP API reference - **Submit endpoint (POST)**: `https://api.atlascloud.ai/api/v1/model/generateAudio` — start an async generation; returns a `prediction_id` - **Poll endpoint (GET)**: `https://api.atlascloud.ai/api/v1/model/prediction/{prediction_id}` — poll this until the prediction finishes - **Model ID**: `elevenlabs/v4/text-to-speech` ## API Information This model can be used via our HTTP API or more conveniently via our client libraries. See the input and output schema below, as well as the usage examples. ### Input Schema The API accepts the following input parameters: - **`model`** (`string`, _required_): Model name. - Default: `"elevenlabs/v4/text-to-speech"` - **`text`** (`string`, _optional_): Text to synthesize into speech audio. Supports inline delivery tags such as [cheerfully], [whispers] and [sighs]. Ignored when `inputs` is given. Hard limit is 10,000 characters. ElevenLabs recommends staying at or below 2,000 characters for reliable generation, but the real constraint is that the upstream connection is cut after about 60 seconds of synthesis; in testing v4 reliably handles up to ~3,000 characters, so keep a request below that to avoid a mid-stream failure. - Default: `"Welcome to Atlas Cloud - One API for All Media AI."` - **`voice`** (`string`, _optional_): Voice for the speech. Pick one of the preset names below, or pass a raw ElevenLabs voice_id (including your own cloned voices), which is forwarded as-is. When `inputs` is given, this is the fallback voice for turns that name none. - Default: `"Roger"` - Options: "Adam", "Alice", "Bella", "Bill", "Brian", "Callum", "Charlie", "Chris", "Daniel", "Eric", "George", "Harry", "Jessica", "Laura", "Liam", "Lily", "Matilda", "River", "Roger", "Sarah", "Will" - **`output_format`** (`string`, _optional_): Output audio format and bitrate. Higher MP3 bitrates and 44.1 kHz PCM/WAV require a higher ElevenLabs plan. - Default: `"mp3_44100_128"` - Options: "mp3_44100_128", "mp3_44100_64", "mp3_22050_32", "opus_48000_128", "pcm_24000", "pcm_16000", "wav_44100", "ulaw_8000", "alaw_8000" - **`stability`** (`number`, _optional_): How steady the delivery is. Lower is more expressive and more variable. - Default: `0.5` - Min: 0 - Max: 1 - **`similarity_boost`** (`number`, _optional_): How closely the output tracks the original voice. - Default: `0.75` - Min: 0 - Max: 1 - **`clone_strength`** (`number`, _optional_): Strength of the voice clone. Applies only to professional voice clones. - Min: 0 - Max: 1 - **`language_code`** (`string`, _optional_): Language code (ISO 639-1) used to enforce a language for the model. - Default: `null` - **`apply_text_normalization`** (`string`, _optional_): Whether numbers, dates and abbreviations are spelled out before synthesis. - Default: `"auto"` - Options: "auto", "on", "off" - **`seed`** (`integer`, _optional_): Seed for best-effort reproducible output. Leave empty for a random seed. - Min: 0 - Max: 4294967295 - **`inputs`** (`array[object]`, _optional_): Multi-speaker dialogue, one object per turn. Overrides `text` and `voice`. At most 10 distinct voices per request, and 10,000 characters across all turns (hard limit). ElevenLabs recommends 2,000 characters combined for reliable generation; the real constraint is the ~60-second upstream cutoff, so in practice keep the combined text at or below ~3,000 characters. - Item properties: - **`text`** (`string`, _required_): What this turn says. Supports the same inline delivery tags as `text`. - **`voice`** (`string`, _optional_): Preset voice name or raw voice_id for this turn. Falls back to the top-level `voice`. - Options: "Adam", "Alice", "Bella", "Bill", "Brian", "Callum", "Charlie", "Chris", "Daniel", "Eric", "George", "Harry", "Jessica", "Laura", "Liam", "Lily", "Matilda", "River", "Roger", "Sarah", "Will" **Required Parameters Example**: ```json { "model": "elevenlabs/v4/text-to-speech" } ``` **Full Example**: ```json { "model": "elevenlabs/v4/text-to-speech", "text": "Welcome to Atlas Cloud - One API for All Media AI.", "voice": "Roger", "output_format": "mp3_44100_128", "stability": 0.5, "similarity_boost": 0.75, "clone_strength": 0, "language_code": null, "apply_text_normalization": "auto", "seed": 0, "inputs": [ { "text": "", "voice": "Adam" } ] } ``` ### Output Schema The API returns the following output format: - **`id`** (`string`, _optional_): Unique identifier for the prediction. - **`model`** (`string`, _optional_): Model ID used for the prediction. - **`status`** (`string`, _optional_): Status of the task: created, processing, completed, or failed. - **`outputs`** (`array[string]`, _optional_): Array of URLs to the generated audio. - **`created_at`** (`string`, _optional_): ISO timestamp of when the request was created. - **`urls`** (`object`, _optional_): Object containing related API endpoints. **Example Response**: ```json { "id": "", "model": "", "status": "", "outputs": [ "" ], "created_at": "", "urls": {} } ``` ## Usage Examples ### cURL ```bash # Step 1: Start generation (async) curl -X POST "https://api.atlascloud.ai/api/v1/model/generateAudio" \ -H "Authorization: Bearer $ATLASCLOUD_API_KEY" \ -H "Content-Type: application/json" \ -d '{ "model": "elevenlabs/v4/text-to-speech", "text": "Welcome to Atlas Cloud - One API for All Media AI.", "voice": "Roger", "output_format": "mp3_44100_128", "stability": 0.5, "similarity_boost": 0.75, "clone_strength": 0, "language_code": null, "apply_text_normalization": "auto", "seed": 0, "inputs": [ { "text": "", "voice": "Adam" } ] }' # Response will contain: {"code": 200, "data": {"id": "prediction_id", "status": "processing"}} # Step 2: Poll for result (replace {prediction_id} with the id returned above) curl -X GET "https://api.atlascloud.ai/api/v1/model/prediction/{prediction_id}" \ -H "Authorization: Bearer $ATLASCLOUD_API_KEY" # Keep polling until status is "completed", "succeeded" or "failed" # When completed, outputs will contain the generated content URL(s) ``` ## Additional Resources ### Documentation - [Model Playground](https://www.atlascloud.ai/models/elevenlabs/v4/text-to-speech) ## About this model _Vendor-supplied description. Any pricing or endpoint mentioned below refers to_ _other platforms — use the Atlas Cloud values above._ ### ElevenLabs v4 Text-to-Speech **ElevenLabs v4** is ElevenLabs' most expressive and emotive text-to-speech model. It turns text into natural speech in 90+ languages, follows inline delivery tags such as `[cheerfully]` and `[whispers]`, and can voice a multi-speaker dialogue in a single request. #### Why Choose This? - **Expressive delivery.** Tuned for emotion and natural intonation — a fit for narration, characters, trailers and conversational agents. - **Inline delivery tags.** Write `[cheerfully]`, `[whispers]`, `[sighs]`, `[laughs]` and similar cues inside the text, and the voice performs them in place. - **Multi-speaker dialogue.** Pass `inputs` with one object per turn to stage a back-and-forth between different voices in one request. - **Preset or cloned voices.** Pick a preset name, or pass any ElevenLabs `voice_id` (including your own cloned voices) and it is forwarded as-is. - **Ready-to-use audio file.** Output is an audio file (MP3 by default). Billed per 1,000 characters of input text. #### Parameters _(Description truncated. Full text on the model page.)_ --- Atlas Cloud — one API for 400+ AI models. Model page: https://www.atlascloud.ai/models/elevenlabs/v4/text-to-speech · Docs: https://www.atlascloud.ai/docs