Generate speech with expressive and realistic voices from xAI
xai/tts/v1
Generate speech with expressive and realistic voices from xAI
Inference
Commercial use
Streaming
Partner
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Convert text to speech using xAI's TTS API.
Supports xAI's built-in voices, inline speech tags for fine-grained delivery control, and output formats from high-fidelity MP3 to telephony-optimized μ-law.
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("xai/tts/v1", {
input: {
text: "Hello! This is xAI text to speech, brought to you by Fal AI."
},
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);This model supports streaming requests. You can stream data directly to the model and get the result in real-time.
import { fal } from "@fal-ai/client";
const stream = await fal.stream("xai/tts/v1", {
input: {
text: "Hello! This is xAI text to speech, brought to you by Fal AI."
}
});
for await (const event of stream) {
console.log(event);
}
const result = await stream.done();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("xai/tts/v1", {
input: {
text: "Hello! This is xAI text to speech, brought to you by Fal AI."
},
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("xai/tts/v1", {
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("xai/tts/v1", {
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.
text string* requiredThe text to convert to speech. Maximum 15,000 characters. Supports speech tags for expressive delivery: inline tags like [laugh], [pause], [sigh] and wrapping tags like <whisper>text</whisper>, <slow>text</slow>.
voice VoiceEnumBuilt-in xAI voice to use for synthesis. Default value: "eve"
Possible enum values: carina, zagan, helix, orion, luna, iris, altair, zenith, perseus, helios, lux, kepler, rigel, cosmo, celeste, ursa, sirius, lumen, castor, naksh, atlas, aurora, liora, ara, eve, leo, rex, sal
language LanguageEnumBCP-47 language code or 'auto' for automatic detection. Supported: en, zh, fr, de, hi, id, it, ja, ko, pt-BR, pt-PT, ru, es-MX, es-ES, tr, vi, bn, ar-EG, ar-SA, ar-AE. Default value: "auto"
Possible enum values: auto, en, ar-EG, ar-SA, ar-AE, bn, zh, fr, de, hi, id, it, ja, ko, pt-BR, pt-PT, ru, es-MX, es-ES, tr, vi
Output format configuration. Defaults to MP3 at 24 kHz / 128 kbps.
enable_safety_checker booleanAuthorized callers may set false to request relaxed screening. Default value: true
{
"text": "Hello! This is xAI text to speech, brought to you by Fal AI.",
"voice": "eve",
"language": "auto",
"enable_safety_checker": true
}The generated audio file.
{
"audio": {
"url": "https://v3b.fal.media/files/b/0a92750b/exZJCm6TDejS5xIulJs2r_xai_tts_output.mp3"
}
}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.
codec CodecEnumAudio codec. Supported: mp3, wav, pcm, mulaw, alaw. Default value: "mp3"
Possible enum values: mp3, wav, pcm, mulaw, alaw
sample_rate SampleRateEnumSample rate in Hz. Default value: "24000"
Possible enum values: 8000, 16000, 22050, 24000, 44100, 48000
bit_rate EnumBit rate in bps. Only applicable for MP3 codec. Defaults to 128000 for MP3.
Possible enum values: 32000, 64000, 96000, 128000, 192000