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Generate 1B
The client provides a convenient way to interact with the model API.
npm install --save @fal-ai/clientThe @fal-ai/serverless-client package has been deprecated in favor of @fal-ai/client. Install the new package and update your imports — see client setup.
Set FAL_KEY as an environment variable in your runtime.
export FAL_KEY="YOUR_API_KEY"The client API handles the API submit protocol. It will handle the request status updates and return the result when the request is completed.
import { fal } from "@fal-ai/client";
const result = await fal.subscribe("fal-ai/tada/1b/text-to-speech", {
input: {
audio_url: "https://storage.googleapis.com/falserverless/example_inputs/reference_audio.wav",
prompt: "The autumn leaves danced gracefully through the crisp morning air, painting the cobblestone streets with shades of amber and gold."
},
logs: true,
onQueueUpdate: (update) => {
if (update.status === "IN_PROGRESS") {
update.logs.map((log) => log.message).forEach(console.log);
}
},
});
console.log(result.data);
console.log(result.requestId);The API uses an API Key for authentication. It is recommended you set the FAL_KEY environment variable in your runtime when possible.
import { fal } from "@fal-ai/client";
fal.config({
credentials: "YOUR_FAL_KEY"
});When running code on the client-side (e.g. in a browser, mobile app or GUI applications), make sure to not expose your FAL_KEY. Instead, use a server-side proxy to make requests to the API. For more information, check out our server-side integration guide.
The client API provides a convenient way to submit requests to the model.
import { fal } from "@fal-ai/client";
const { request_id } = await fal.queue.submit("fal-ai/tada/1b/text-to-speech", {
input: {
audio_url: "https://storage.googleapis.com/falserverless/example_inputs/reference_audio.wav",
prompt: "The autumn leaves danced gracefully through the crisp morning air, painting the cobblestone streets with shades of amber and gold."
},
webhookUrl: "https://optional.webhook.url/for/results",
});You can fetch the status of a request to check if it is completed or still in progress.
import { fal } from "@fal-ai/client";
const status = await fal.queue.status("fal-ai/tada/1b/text-to-speech", {
requestId: "764cabcf-b745-4b3e-ae38-1200304cf45b",
logs: true,
});Once the request is completed, you can fetch the result. See the Output Schema for the expected result format.
import { fal } from "@fal-ai/client";
const result = await fal.queue.result("fal-ai/tada/1b/text-to-speech", {
requestId: "764cabcf-b745-4b3e-ae38-1200304cf45b"
});
console.log(result.data);
console.log(result.requestId);Some attributes in the API accept file URLs as input. Whenever that's the case you can pass your own URL or a Base64 data URI.
You can pass a Base64 data URI as a file input. The API will handle the file decoding for you. Keep in mind that for large files, this alternative although convenient can impact the request performance.
You can also pass your own URLs as long as they are publicly accessible. Be aware that some hosts might block cross-site requests, rate-limit, or consider the request as a bot.
We provide a convenient file storage that allows you to upload files and use them in your requests. You can upload files using the client API and use the returned URL in your requests.
import { fal } from "@fal-ai/client";
const file = new File(["Hello, World!"], "hello.txt", { type: "text/plain" });
const url = await fal.storage.upload(file);The client will auto-upload the file for you if you pass a binary object (e.g. File, Data).
Read more about file handling in our file upload guide.
audio_url string* requiredURL of the reference audio file for voice cloning. The model will replicate this speaker's voice characteristics.
transcript stringTranscript of the reference audio. For non-English audio, providing a transcript is required since the built-in ASR is English-only. Default value: ""
prompt string* requiredThe text to synthesize into speech using the reference speaker's voice.
language LanguageEnumLanguage for text alignment. Use the appropriate code for non-English synthesis. Default value: "en"
Possible enum values: en, ar, ch, de, es, fr, it, ja, pl, pt
num_extra_steps integerNumber of extra autoregressive steps for speech continuation beyond the input text. Useful for generating trailing prosody or silence.
temperature floatSampling temperature for text token generation. Must be greater than 0. Higher values produce more varied output. Default value: 0.6
top_p floatTop-p (nucleus) sampling parameter for text generation. Default value: 0.9
repetition_penalty floatPenalty applied to repeated tokens during generation. Default value: 1.1
acoustic_cfg_scale floatClassifier-free guidance scale for acoustic feature generation. Default value: 1.6
noise_temperature floatTemperature for noise in the flow matching diffusion process. Default value: 0.9
num_inference_steps integerNumber of ODE solver steps for flow matching acoustic generation. More steps improve quality at the cost of speed. Default value: 20
speed_up_factor floatFactor to speed up or slow down the generated speech. Values > 1.0 speed up, < 1.0 slow down. Default value: 1
output_format OutputFormatEnumThe format of the output audio file. Default value: "wav"
Possible enum values: wav, mp3
enable_safety_checker booleanAuthorized callers may set false to request relaxed screening. Default value: true
{
"audio_url": "https://storage.googleapis.com/falserverless/example_inputs/reference_audio.wav",
"transcript": "Some call me nature, others call me mother nature.",
"prompt": "The autumn leaves danced gracefully through the crisp morning air, painting the cobblestone streets with shades of amber and gold.",
"language": "en",
"temperature": 0.6,
"top_p": 0.9,
"repetition_penalty": 1.1,
"acoustic_cfg_scale": 1.6,
"noise_temperature": 0.9,
"num_inference_steps": 20,
"speed_up_factor": 1,
"output_format": "wav",
"enable_safety_checker": true
}The generated speech audio file.
{
"audio": {
"url": "https://v3b.fal.media/files/b/0a91e55e/HUVJsjW6QoDUBfg6HdM5e_B2R8G4X4.wav"
}
}url string* requiredThe URL where the file can be downloaded from.
content_type stringThe mime type of the file.
file_name stringThe name of the file. It will be auto-generated if not provided.
file_size integerThe size of the file in bytes.
duration floatThe duration of the audio
channels integerThe number of channels in the audio
sample_rate integerThe sample rate of the audio