> For clean Markdown of any page, append `.md` to the page URL. > For a complete documentation index, see https://docs.sarvam.ai/llms.txt. > For full documentation content in one file, see https://docs.sarvam.ai/llms-full.txt. > For AI client integration (Claude Code, Cursor, etc.), connect to the MCP server at https://docs.sarvam.ai/_mcp/server. # Migrating Text-to-Speech from ElevenLabs to Sarvam > Endpoint, parameter, and response-format differences between ElevenLabs and Sarvam's Text-to-Speech API, with before/after code for REST, streaming, and pronunciation dictionaries. *Last updated: July 15, 2026* This guide covers migrating ElevenLabs text-to-speech API calls to Sarvam. If you're building a full voice agent rather than replacing individual TTS calls, start from the [LiveKit](/api/integration/build-voice-agent-with-live-kit) or [Pipecat](/api/integration/build-voice-agent-with-pipecat) voice agent build guides instead: they aren't a 1:1 API swap and aren't covered here. > **Tip** > > **In short:** swap `voice_id` for `speaker`, add a required `language_code`, and change your response handling: ElevenLabs returns raw audio bytes, Sarvam returns JSON with base64-encoded audio in an `audios` array. Sarvam's structured response is what makes it easy to pair audio with per-request metadata; that decode step is the change most migrations look for first. ## Quick start Base URL and auth header change the same way for every ElevenLabs migration, so they're folded in here rather than in a separate page: | | ElevenLabs | Sarvam | | ------------------- | --------------------------- | ----------------------- | | Base URL | `https://api.elevenlabs.io` | `https://api.sarvam.ai` | | Auth header | `xi-api-key` | `api-subscription-key` | | Auth failure status | `401` | `403` | With that, replace the synthesis call and add the required language code: #### Before (ElevenLabs) #### Python ```python from elevenlabs import ElevenLabs client = ElevenLabs(api_key="YOUR_ELEVENLABS_API_KEY") audio = client.text_to_speech.convert( voice_id="21m00Tcm4TlvDq8ikWAM", model_id="eleven_multilingual_v2", text="Welcome to our platform!", voice_settings={ "stability": 0.5, "similarity_boost": 0.75, "style": 0.0, "use_speaker_boost": True, "speed": 1.0, }, ) with open("output.mp3", "wb") as f: for chunk in audio: f.write(chunk) ``` #### JavaScript ```javascript import { ElevenLabsClient } from "@elevenlabs/elevenlabs-js"; import fs from "fs"; const client = new ElevenLabsClient({ apiKey: "YOUR_ELEVENLABS_API_KEY" }); const audio = await client.textToSpeech.convert("21m00Tcm4TlvDq8ikWAM", { text: "Welcome to our platform!", modelId: "eleven_multilingual_v2", voiceSettings: { stability: 0.5, similarityBoost: 0.75, style: 0.0, useSpeakerBoost: true, speed: 1.0, }, }); const reader = audio.getReader(); const chunks = []; while (true) { const { done, value } = await reader.read(); if (done) break; chunks.push(value); } fs.writeFileSync("output.mp3", Buffer.concat(chunks.map((c) => Buffer.from(c)))); ``` #### cURL ```bash curl -X POST "https://api.elevenlabs.io/v1/text-to-speech/21m00Tcm4TlvDq8ikWAM" \ -H "xi-api-key: YOUR_ELEVENLABS_API_KEY" \ -H "Content-Type: application/json" \ -d '{ "text": "Welcome to our platform!", "model_id": "eleven_multilingual_v2", "voice_settings": {"stability": 0.5, "similarity_boost": 0.75} }' \ --output output.mp3 ``` #### After (Sarvam) #### Python ```python import base64 from sarvamai import SarvamAI client = SarvamAI(api_subscription_key="YOUR_SARVAM_API_KEY") response = client.text_to_speech.convert( text="Welcome to our platform!", language_code="en-IN", speaker="shubh", model="bulbul:v3", pace=1.0, ) with open("output.wav", "wb") as f: f.write(base64.b64decode("".join(response.audios))) ``` #### JavaScript ```javascript import { SarvamAIClient } from "sarvamai"; import fs from "fs"; const client = new SarvamAIClient({ apiSubscriptionKey: "YOUR_SARVAM_API_KEY" }); const response = await client.textToSpeech.convert({ text: "Welcome to our platform!", language_code: "en-IN", speaker: "shubh", model: "bulbul:v3", pace: 1.0, }); fs.writeFileSync("output.wav", Buffer.from(response.audios.join(""), "base64")); ``` #### cURL ```bash curl -X POST https://api.sarvam.ai/text-to-speech \ -H "api-subscription-key: YOUR_SARVAM_API_KEY" \ -H "Content-Type: application/json" \ -d '{ "text": "Welcome to our platform!", "language_code": "en-IN", "speaker": "shubh", "model": "bulbul:v3" }' ``` > **Note** > > ElevenLabs' Python and JavaScript SDKs hand back an iterable/stream of audio chunks you can write directly. Sarvam's `convert()` returns a JSON object; the audio lives in `response.audios` as a list of base64 strings, one per input text. Join and decode before writing to disk, or use the Python SDK's `sarvamai.play.save()` helper, which does this for you. The REST response is JSON with a base64 `audios` array, not a file. Decode `.audios[0]` before writing it out; see the [REST API guide](/api/api-guides-tutorials/text-to-speech/rest-api) for the full decode snippet. The rest of this page covers the full endpoint and parameter mapping, streaming, pronunciation dictionaries, and common mistakes. ## Endpoint map > **Tip** > > The tables below aren't a checklist to apply field-by-field: Quick Start above already shows the whole call swapped over in one go. Use these tables as a reference for what changed and why, not as a sequence of edits to make yourself. | | ElevenLabs | Sarvam | | --------------------- | --------------------------------------------------------- | ------------------------------------------------------------------------------------------------------------------------ | | Synchronous synthesis | `POST /v1/text-to-speech/{voice_id}` | `POST /text-to-speech` | | HTTP streaming | `POST /v1/text-to-speech/{voice_id}/stream` | `POST /text-to-speech/stream` | | WebSocket streaming | `GET wss://.../v1/text-to-speech/{voice_id}/stream-input` | `GET /text-to-speech/ws` | | Voice discovery | `GET /v2/voices` (paginated, searchable) | No API call needed; speaker names are a fixed list on the [Voices](/api/api-guides-tutorials/text-to-speech/voices) page | ## Parameter concept map | ElevenLabs | Sarvam | Note | | ------------------------------------------------------------------------------ | ---------------------------------------------------------------------------------------------- | --------------------------------------------------------------------------------------------------------------------------------------------------------- | | `voice_id` (opaque ID, e.g. `21m00Tcm4TlvDq8ikWAM`) | `speaker` (plain lowercase name, e.g. `shubh`, `priya`) | No lookup call required, pick a name directly from the [Voices](/api/api-guides-tutorials/text-to-speech/voices) page | | `model_id` (`eleven_multilingual_v2`, `eleven_flash_v2_5`, `eleven_v3`, etc.) | `model` (`bulbul:v2` or `bulbul:v3`) | Two model versions total, not a family of speed/quality tiers | | `voice_settings.stability` | Built into the voice | Every Bulbul speaker is pre-tuned for consistent delivery, so there's no separate dial to calibrate | | `voice_settings.similarity_boost` | Not needed | Sarvam speakers are production-ready studio voices rather than per-request clones, so there's nothing to tune | | `voice_settings.style` | Speaker choice | Pick the speaker whose baseline delivery already matches the expressiveness you want; see [Voices](/api/api-guides-tutorials/text-to-speech/voices) | | `voice_settings.use_speaker_boost` | Not needed | Clarity is tuned in by default on every speaker | | `voice_settings.speed` (default `1.0`) | `pace` (default `1.0`, range `0.5` to `2.0` on v3, `0.3` to `3.0` on v2) | Same idea, wider range on Sarvam's side | | `language_code` (optional, most models infer language from voice/model) | `language_code` (**required** on every request) | Guarantees the right pronunciation and prosody on every call, which matters most for code-mixed Indian-language text | | `output_format` (single string, e.g. `mp3_44100_128`) | `speech_sample_rate` + `output_audio_codec` (separate params, available on REST and streaming) | Defaults to WAV at 24000 Hz; set `output_audio_codec` (`mp3`, `opus`, `flac`, `aac`, `wav`, etc.) and `speech_sample_rate` independently to change either | | `pronunciation_dictionary_locators` | `dict_id` | Both are scoped and reusable across requests, format differs, see [Pronunciation dictionary](#pronunciation-dictionary) below | | Response: raw binary audio (`application/octet-stream` or per `output_format`) | Response: JSON, audio as base64 strings in `audios` | Structured response makes it straightforward to pair audio with per-request metadata; decode `.audios[0]` before writing to disk | > **Note** > > `pitch` and `loudness` give you fine-grained tone and volume control on **`bulbul:v2`**. On **`bulbul:v3`**, which adds a larger voice set and stronger code-mixed handling, tone comes from speaker choice instead, so pick a speaker whose baseline delivery already fits rather than reaching for these two params. ## Streaming | | ElevenLabs | Sarvam | | ---------------- | -------------------------------------------------------------------------------------------------------------------------------------------------- | ---------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------- | | HTTP streaming | `POST /v1/text-to-speech/{voice_id}/stream` | [HTTP Stream API](/api/api-guides-tutorials/text-to-speech/streaming-api/http-stream) (`POST /text-to-speech/stream`): both return audio progressively over one request, no persistent connection | | WebSocket | `.../stream-input`: initial message carrying `voice_settings`, then `SendText` messages (optional `flush` flag), closed with an empty-text message | [WebSocket API](/api/api-guides-tutorials/text-to-speech/streaming-api/web-socket): `ws.configure(...)` once, then repeated `ws.convert(text)` and `ws.flush()` on the same connection | | Character limits | A single large call, e.g. up to 10,000 characters on `eleven_multilingual_v2` | WebSocket up to 2500 chars/message (under 500 recommended for lowest latency), REST up to 2500 on `bulbul:v3` (1500 on `bulbul:v2`), HTTP streaming up to 3500 regardless of model, may need chunking logic that didn't previously exist | ## Pronunciation dictionary Both platforms let you fix mispronounced brand names and acronyms without retraining a model, but the mechanism differs: | | ElevenLabs | Sarvam | | ----------------- | ----------------------------------------------------------------- | ------------------------------------------------------------------------------------------------------------------- | | Rule types | Phoneme rules (IPA) and word-alias rules | Word-alias (plain text substitution), simple to author and audit | | Scope | Referenced via `pronunciation_dictionary_locators` in the request | Referenced via a single `dict_id` per request | | Language handling | Rules can be tied to specific words regardless of language | Rules are nested per `language_code`; only entries matching the request's language apply | | Limits | Varies by plan | 10 dictionaries per user, 100 words per dictionary, 1 MB per upload, 1 dictionary per request | | Model support | Available across ElevenLabs' model tiers | **`bulbul:v3` only**: a request can't combine a pronunciation dictionary with the v2-only `pitch`/`loudness` params | If your ElevenLabs dictionary relies on IPA phoneme rules for precise pronunciation control, plan to rewrite it: Sarvam dictionaries use plain word-to-word text replacements (e.g. `"NAIC": "N A I C"`), which are simpler to author and audit than phonetic transcriptions. See the [Pronunciation Dictionary guide](/api/api-guides-tutorials/text-to-speech/pronunciation-dictionary) for the full format and upload flow. ## What's different by design * **Ready-to-use voices out of the box.** Sarvam ships a curated, named set of 30+ Bulbul v3 voices, professionally tuned and ready to call immediately, with no per-request cloning or training step to manage. If your ElevenLabs setup relies on cloned or custom voices, the [Voice Cloning migration guide](/api/migrations/from-elevenlabs/voice-cloning) covers creating a saved voice and generating speech with its `voice_id`. * **Explicit language targeting.** Every Sarvam request carries `language_code`, so pronunciation and prosody are correct by design on every call, especially valuable for Hindi, Hinglish, and other code-mixed Indian-language text where auto-detection is prone to guessing wrong. * **A simpler tuning surface.** Tone and delivery come from picking the right speaker plus `pace` (and `pitch`/`loudness` on v2), instead of calibrating `stability`, `similarity_boost`, `style`, and `use_speaker_boost` separately. Fewer knobs, less trial and error to land on a voice that sounds right. * **Indian language depth is Sarvam's specific strength.** Sarvam covers Hindi plus 9 other Indian languages (Bengali, Tamil, Telugu, Kannada, Malayalam, Marathi, Gujarati, Punjabi, Odia), natively tuned for code-mixed input like Hinglish. If your product needs those languages, this is the reason to migrate, not just a side effect of it. * **Instant voice discovery.** Every speaker is listed with audio previews on the [Voices](/api/api-guides-tutorials/text-to-speech/voices) page: no API call, no pagination, nothing to query. ## Full example A small wrapper function, before and after, showing the complete set of changes together: #### Before (ElevenLabs) #### Python ```python from elevenlabs import ElevenLabs client = ElevenLabs(api_key="YOUR_ELEVENLABS_API_KEY") def synthesize(text: str, out_path: str): audio = client.text_to_speech.convert( voice_id="21m00Tcm4TlvDq8ikWAM", model_id="eleven_multilingual_v2", text=text, voice_settings={"stability": 0.5, "similarity_boost": 0.75}, ) with open(out_path, "wb") as f: for chunk in audio: f.write(chunk) ``` #### JavaScript ```javascript import { ElevenLabsClient } from "@elevenlabs/elevenlabs-js"; import fs from "fs"; const client = new ElevenLabsClient({ apiKey: "YOUR_ELEVENLABS_API_KEY" }); async function synthesize(text, outPath) { const audio = await client.textToSpeech.convert("21m00Tcm4TlvDq8ikWAM", { text, modelId: "eleven_multilingual_v2", voiceSettings: { stability: 0.5, similarityBoost: 0.75 }, }); const reader = audio.getReader(); const chunks = []; while (true) { const { done, value } = await reader.read(); if (done) break; chunks.push(value); } fs.writeFileSync(outPath, Buffer.concat(chunks.map((c) => Buffer.from(c)))); } ``` #### cURL ```bash synthesize() { local text="$1" out_path="$2" curl -sS -X POST "https://api.elevenlabs.io/v1/text-to-speech/21m00Tcm4TlvDq8ikWAM" \ -H "xi-api-key: YOUR_ELEVENLABS_API_KEY" \ -H "Content-Type: application/json" \ -d "{\"text\": \"$text\", \"model_id\": \"eleven_multilingual_v2\", \"voice_settings\": {\"stability\": 0.5, \"similarity_boost\": 0.75}}" \ --output "$out_path" } ``` #### After (Sarvam) #### Python ```python import base64 from sarvamai import SarvamAI from sarvamai.core.api_error import ApiError client = SarvamAI(api_subscription_key="YOUR_SARVAM_API_KEY") def synthesize(text: str, out_path: str, language_code: str = "en-IN") -> None: try: response = client.text_to_speech.convert( text=text, language_code=language_code, speaker="shubh", model="bulbul:v3", ) except ApiError as e: if e.status_code == 403: raise RuntimeError("Invalid API key. Check your credentials.") from e elif e.status_code == 429: raise RuntimeError("Rate limit exceeded. Wait and retry.") from e elif e.status_code == 503: raise RuntimeError("Service overloaded. Retry with backoff.") from e raise with open(out_path, "wb") as f: f.write(base64.b64decode("".join(response.audios))) ``` #### JavaScript ```javascript import { SarvamAIClient, SarvamAIError } from "sarvamai"; import fs from "fs"; const client = new SarvamAIClient({ apiSubscriptionKey: "YOUR_SARVAM_API_KEY" }); async function synthesize(text, outPath, languageCode = "en-IN") { let response; try { response = await client.textToSpeech.convert({ text, language_code: languageCode, speaker: "shubh", model: "bulbul:v3", }); } catch (e) { if (e instanceof SarvamAIError) { if (e.statusCode === 403) throw new Error("Invalid API key. Check your credentials."); if (e.statusCode === 429) throw new Error("Rate limit exceeded. Wait and retry."); if (e.statusCode === 503) throw new Error("Service overloaded. Retry with backoff."); } throw e; } fs.writeFileSync(outPath, Buffer.from(response.audios.join(""), "base64")); } ``` #### cURL ```bash synthesize() { local text="$1" out_path="$2" language_code="${3:-en-IN}" local body status audio_b64 body=$(curl -sS -w '\n%{http_code}' -X POST https://api.sarvam.ai/text-to-speech \ -H "api-subscription-key: YOUR_SARVAM_API_KEY" \ -H "Content-Type: application/json" \ -d "{\"text\": \"$text\", \"language_code\": \"$language_code\", \"speaker\": \"shubh\", \"model\": \"bulbul:v3\"}") status="${body##*$'\n'}" case "$status" in 403) echo "Invalid API key. Check your credentials." >&2; return 1 ;; 429) echo "Rate limit exceeded. Wait and retry." >&2; return 1 ;; 503) echo "Service overloaded. Retry with backoff." >&2; return 1 ;; esac # Minimal single-value extraction; use a real JSON parser for production code. audio_b64=$(echo "${body%$'\n'*}" | grep -o '"audios":\["[^"]*"' | cut -d'"' -f4) echo "$audio_b64" | base64 -d > "$out_path" } ``` ## Common mistakes #### Writing the response body directly as an audio file The single most common migration bug. ElevenLabs' REST response is the audio file itself; Sarvam's is JSON. Code that does `f.write(response.content)` unmodified will produce a file full of JSON text, not audio. Decode `response.audios[0]` from base64 first. #### Forgetting language\_code It's required on every request, by design: this is what guarantees Sarvam applies the correct pronunciation and prosody instead of guessing from the `speaker` name. Include it from the start rather than treating it as optional. #### Trying to tune pace/pitch instead of picking the right speaker `pace` and `pitch` aren't drop-in replacements for `stability` or `style`. Rather than compensating with those params, pick a speaker whose baseline delivery already matches what you need; see the [Voices](/api/api-guides-tutorials/text-to-speech/voices) page for per-speaker tone descriptions. #### Reusing pitch/loudness on bulbul:v3 Both params are accepted syntactically but only take effect on `bulbul:v2`. If output sounds unchanged after setting them, confirm which model version the request is actually using. #### Porting an IPA-based pronunciation dictionary as-is Sarvam's dictionary format is plain word-to-word substitution, not phoneme rules. An ElevenLabs dictionary built on IPA transcriptions needs to be rewritten as text replacements, not just re-uploaded. ## See also * [Migration overview](/api/migrations/from-elevenlabs/overview): base URL, auth, and SDK client changes * [Migrating Speech-to-Text](/api/migrations/from-elevenlabs/speech-to-text) * [Which Text-to-Speech API to Use](/api/api-guides-tutorials/text-to-speech/which-api-to-use) * [TTS Best Practices](/api/api-guides-tutorials/text-to-speech/best-practices) * [Voices](/api/api-guides-tutorials/text-to-speech/voices) * [Pronunciation Dictionary](/api/api-guides-tutorials/text-to-speech/pronunciation-dictionary) * [Errors & Troubleshooting](/api/getting-started/errors-troubleshooting) > Endpoint, parameter, and response-format differences between ElevenLabs and Sarvam's Text-to-Speech API, with before/after code for REST, streaming, and pronunciation dictionaries.