Migrate to Fish Audio

Your SDK	Base URL
OpenAI	`https://api.fish.audio/compat/v1`
OpenRouter	`https://api.fish.audio/compat/api/v1`
ElevenLabs	`https://api.fish.audio/compat/elevenlabs`
Groq	`https://api.fish.audio/compat`

OpenAI
OpenRouter
ElevenLabs
Groq

Set your API key

Store your Fish Audio API key as an environment variable:

export FISH_AUDIO_API_KEY="your_api_key"

Swap the base URL and generate

import os
from openai import OpenAI

client = OpenAI(
    base_url="https://api.fish.audio/compat/v1",
    api_key=os.environ["FISH_AUDIO_API_KEY"],
)

with client.audio.speech.with_streaming_response.create(
    model="fish-audio/s2.1-pro",
    input="Hello from Fish Audio!",
    voice="",  # "" = default voice; see Voices below to pick one
    response_format="mp3",
) as response:
    response.stream_to_file("hello.mp3")

import OpenAI from "openai";
import fs from "node:fs";

const client = new OpenAI({
  baseURL: "https://api.fish.audio/compat/v1",
  apiKey: process.env.FISH_AUDIO_API_KEY,
});

const response = await client.audio.speech.create({
  model: "fish-audio/s2.1-pro",
  input: "Hello from Fish Audio!",
  voice: "", // "" = default voice; see Voices below to pick one
  response_format: "mp3",
});
fs.writeFileSync("hello.mp3", Buffer.from(await response.arrayBuffer()));

curl https://api.fish.audio/compat/v1/audio/speech \
  -H "Authorization: Bearer $FISH_AUDIO_API_KEY" \
  -H "Content-Type: application/json" \
  -d '{"model": "fish-audio/s2.1-pro",
       "input": "Hello from Fish Audio!",
       "response_format": "mp3"}' \
  --output hello.mp3

Full guide: Migrate from OpenAI, covering transcription, chat audio, the Realtime WebSocket, and what each feature supports.

Set your API key

Store your Fish Audio API key as an environment variable:

export FISH_AUDIO_API_KEY="your_api_key"

Swap the base URL and generate

From Python, use the OpenAI SDK against the same /api/v1 base; that is how OpenRouter itself is used from Python.

import { OpenRouter } from "@openrouter/sdk";
import fs from "node:fs";

const client = new OpenRouter({
  apiKey: process.env.FISH_AUDIO_API_KEY,
  serverURL: "https://api.fish.audio/compat/api/v1",
});

const stream = await client.tts.createSpeech({
  speechRequest: {
    model: "fish-audio/s2.1-pro",
    input: "Hello from Fish Audio!",
    responseFormat: "mp3",
  },
});
const chunks = [];
for await (const chunk of stream) chunks.push(chunk);
fs.writeFileSync("hello.mp3", Buffer.concat(chunks));

import os
from openai import OpenAI

client = OpenAI(
    base_url="https://api.fish.audio/compat/api/v1",
    api_key=os.environ["FISH_AUDIO_API_KEY"],
)

with client.audio.speech.with_streaming_response.create(
    model="fish-audio/s2.1-pro",
    input="Hello from Fish Audio!",
    voice="",  # "" = default voice; see Voices below to pick one
    response_format="mp3",
) as response:
    response.stream_to_file("hello.mp3")

curl https://api.fish.audio/compat/api/v1/audio/speech \
  -H "Authorization: Bearer $FISH_AUDIO_API_KEY" \
  -H "Content-Type: application/json" \
  -d '{"model": "fish-audio/s2.1-pro",
       "input": "Hello from Fish Audio!",
       "response_format": "mp3"}' \
  --output hello.mp3

Full guide: Migrate from OpenRouter, covering transcription, the model catalog, and what each feature supports.

Set your API key

Store your Fish Audio API key as an environment variable:

export FISH_AUDIO_API_KEY="your_api_key"

Swap the base URL and generate

The key is sent as the standard xi-api-key header:

import os
from elevenlabs import ElevenLabs

client = ElevenLabs(
    base_url="https://api.fish.audio/compat/elevenlabs",
    api_key=os.environ["FISH_AUDIO_API_KEY"],
)

audio = b"".join(client.text_to_speech.convert(
    voice_id="default",  # "default" = default voice; see Voices below
    text="Hello from Fish Audio!",
    model_id="fish-audio/s2.1-pro",
    output_format="mp3_44100_128",
))
open("hello.mp3", "wb").write(audio)

import { ElevenLabsClient } from "@elevenlabs/elevenlabs-js";
import fs from "node:fs";

const client = new ElevenLabsClient({
  baseUrl: "https://api.fish.audio/compat/elevenlabs",
  apiKey: process.env.FISH_AUDIO_API_KEY,
});

// "default" = default voice; see Voices below to pick one
const stream = await client.textToSpeech.convert("default", {
  text: "Hello from Fish Audio!",
  modelId: "fish-audio/s2.1-pro",
  outputFormat: "mp3_44100_128",
});
const chunks = [];
for await (const chunk of stream) chunks.push(chunk);
fs.writeFileSync("hello.mp3", Buffer.concat(chunks));

curl "https://api.fish.audio/compat/elevenlabs/v1/text-to-speech/default?output_format=mp3_44100_128" \
  -H "xi-api-key: $FISH_AUDIO_API_KEY" \
  -H "Content-Type: application/json" \
  -d '{"text": "Hello from Fish Audio!",
       "model_id": "fish-audio/s2.1-pro"}' \
  --output hello.mp3

Full guide: Migrate from ElevenLabs, covering speech-to-text, timestamps, realtime streaming, your voice library, and what each feature supports.

Set your API key

Store your Fish Audio API key as an environment variable:

export FISH_AUDIO_API_KEY="your_api_key"

Swap the base URL and generate

The Groq SDK appends /openai/v1 itself, so give it the bare /compat base:

import os
from groq import Groq

client = Groq(
    base_url="https://api.fish.audio/compat",
    api_key=os.environ["FISH_AUDIO_API_KEY"],
)

resp = client.audio.speech.create(
    model="fish-audio/s2.1-pro",
    input="Hello from Fish Audio!",
    voice="",  # "" = default voice; see Voices below to pick one
    response_format="mp3",
)
open("hello.mp3", "wb").write(resp.read())

import Groq from "groq-sdk";
import fs from "node:fs";

const client = new Groq({
  apiKey: process.env.FISH_AUDIO_API_KEY,
  baseURL: "https://api.fish.audio/compat",
});

const resp = await client.audio.speech.create({
  model: "fish-audio/s2.1-pro",
  input: "Hello from Fish Audio!",
  voice: "", // "" = default voice; see Voices below to pick one
  response_format: "mp3",
});
fs.writeFileSync("hello.mp3", Buffer.from(await resp.arrayBuffer()));

curl https://api.fish.audio/compat/openai/v1/audio/speech \
  -H "Authorization: Bearer $FISH_AUDIO_API_KEY" \
  -H "Content-Type: application/json" \
  -d '{"model": "fish-audio/s2.1-pro",
       "input": "Hello from Fish Audio!",
       "response_format": "mp3"}' \
  --output hello.mp3

Full guide: Migrate from Groq, covering transcription, the model catalog, and what each feature supports.

From a framework

Frameworks that speak the OpenAI protocol work the same way: point them at /compat/v1:

import base64
import os
from langchain_openai import ChatOpenAI

llm = ChatOpenAI(
    base_url="https://api.fish.audio/compat/v1",
    api_key=os.environ["FISH_AUDIO_API_KEY"],
    model="fish-audio/s2.1-pro",
    model_kwargs={"modalities": ["text", "audio"],
                  "audio": {"voice": "", "format": "mp3"}},
)

resp = llm.invoke("Hello from Fish Audio!")
audio = base64.b64decode(resp.additional_kwargs["audio"]["data"])
open("hello.mp3", "wb").write(audio)

import { experimental_generateSpeech as generateSpeech } from "ai";
import { createOpenAI } from "@ai-sdk/openai";
import fs from "node:fs";

const openai = createOpenAI({
  baseURL: "https://api.fish.audio/compat/v1",
  apiKey: process.env.FISH_AUDIO_API_KEY,
});

const { audio } = await generateSpeech({
  model: openai.speech("fish-audio/s2.1-pro"),
  text: "Hello from Fish Audio!",
  voice: "",
  outputFormat: "mp3",
});
fs.writeFileSync("hello.mp3", audio.uint8Array);

Building a voice agent with Pipecat or LiveKit? Fish Audio has native integrations for those.

Models

Model	What it is
`fish-audio/s2.1-pro`	Production multilingual TTS with voice cloning (recommended)
`fish-audio/s2.1-pro-free`	Free tier of S2.1 Pro, for prototyping (no latency guarantee)
`fish-audio/s2-pro`	Expressive TTS for narration and multi-speaker content
`fish-audio/s1`	Multilingual TTS with emotion control
`fish-audio/transcribe-1`	Multilingual speech-to-text with word-level timestamps

transcribe-1 needs no language hint. The language field in a transcription response echoes what you sent: empty when you sent none, never a detection result (the ElevenLabs protocol echoes language_code the same way). For speaker turns, long recordings, and inline emotion cues, use transcribe-1-pro on the native Speech to Text API.

Voices

The examples above use the model’s default voice. To pick a specific one, pass a voice ID: browse the Voice Library and copy the id of any voice, or make your own with Voice Cloning or Voice Design. Vendor preset names (nova, echo, Rachel, …) don’t exist here.

voice="9a9cf47702da476aa4629e2506d4a857"      # OpenAI / OpenRouter / Groq
voice_id="9a9cf47702da476aa4629e2506d4a857"   # ElevenLabs

Going further

Wondering whether an option you rely on is supported? See Compatibility. Starting fresh instead? The native API and official SDK expose every Fish Audio capability directly.

Get Started

Core Features

Platform (Web App)

Models & Pricing

Migrate to Fish Audio

From a framework

Models

Voices

Going further

​From a framework

​Models

​Voices

​Going further

From a framework

Models

Voices

Going further