# Create speech with timing

POST https://api.elevenlabs.io/v1/text-to-speech//with-timestamps
Content-Type: application/json

Generate speech from text with precise character-level timing information for audio-text synchronization.

Reference: https://elevenlabs.io/docs/api-reference/text-to-speech/convert-with-timestamps

**Servers**

- `https://api.elevenlabs.io` (Production, default)
- `https://api.us.elevenlabs.io` (Production US)
- `https://api.eu.residency.elevenlabs.io` (Production EU)
- `https://api.in.residency.elevenlabs.io` (Production India)
- `https://api.sg.residency.elevenlabs.io` (Production Singapore)

## Request

### Path parameters

- `voice_id` (string, required) — Voice ID to be used, you can use https://api.elevenlabs.io/v1/voices to list all the available voices.

### Query parameters

- `enable_logging` (boolean, optional, default: true) — When enable\_logging is set to false zero retention mode will be used for the request. This will mean history features are unavailable for this request, including request stitching. Zero retention mode may only be used by enterprise customers.
- `optimize_streaming_latency` (integer, optional, nullable, deprecated) — You can turn on latency optimizations at some cost of quality. The best possible final latency varies by model. Possible values: 0 - default mode (no latency optimizations) 1 - normal latency optimizations (about 50% of possible latency improvement of option 3) 2 - strong latency optimizations (about 75% of possible latency improvement of option 3) 3 - max latency optimizations 4 - max latency optimizations, but also with text normalizer turned off for even more latency savings (best latency, but can mispronounce eg numbers and dates). Defaults to None.
- `output_format` (enum, optional, default: mp3\_44100\_128) — Output format of the generated audio. Formatted as codec\_sample\_rate\_bitrate. So an mp3 with 22.05kHz sample rate at 32kbs is represented as mp3\_22050\_32. MP3 with 192kbps bitrate requires you to be subscribed to Creator tier or above. PCM and WAV formats with 44.1kHz sample rate requires you to be subscribed to Pro tier or above. Note that the μ-law format (sometimes written mu-law, often approximated as u-law) is commonly used for Twilio audio inputs.
  - Allowed values: `alaw_8000`, `mp3_22050_32`, `mp3_24000_48`, `mp3_44100_128`, `mp3_44100_192`, `mp3_44100_32`, `mp3_44100_64`, `mp3_44100_96`, `opus_48000_128`, `opus_48000_192`, `opus_48000_32`, `opus_48000_64`, `opus_48000_96`, `pcm_16000`, `pcm_22050`, `pcm_24000`, `pcm_32000`, `pcm_44100`, `pcm_48000`, `pcm_8000`, `ulaw_8000`, `wav_16000`, `wav_22050`, `wav_24000`, `wav_32000`, `wav_44100`, `wav_48000`, `wav_8000`

**Body (application/json)**

This endpoint expects a Body\_text\_to\_speech\_full\_with\_timestamps.

- `text` (string, required) — The text that will get converted into speech.
- `model_id` (string, optional, default: eleven\_multilingual\_v2) — Identifier of the model that will be used, you can query them using GET /v1/models. The model needs to have support for text to speech, you can check this using the can\_do\_text\_to\_speech property.
- `language_code` (string, optional, nullable) — Language code (ISO 639-1) used to enforce a language for the model and text normalization. If the model does not support the provided language code, it will be ignored. This parameter is not supported for multilingual\_v2 models.
- `voice_settings` (VoiceSettingsResponseModel, optional, nullable) — Voice settings overriding stored settings for the given voice. They are applied only on the given request.
- `pronunciation_dictionary_locators` (list of PronunciationDictionaryVersionLocatorRequestModel, optional) — A list of pronunciation dictionary locators (id, version\_id) to be applied to the text. They will be applied in order. You may have up to 3 locators per request
- `seed` (integer, optional, nullable) — If specified, our system will make a best effort to sample deterministically, such that repeated requests with the same seed and parameters should return the same result. Determinism is not guaranteed. Must be integer between 0 and 4294967295.
- `previous_text` (string, optional, nullable) — The text that came before the text of the current request. Can be used to improve the speech's continuity when concatenating together multiple generations or to influence the speech's continuity in the current generation.
- `next_text` (string, optional, nullable) — The text that comes after the text of the current request. Can be used to improve the speech's continuity when concatenating together multiple generations or to influence the speech's continuity in the current generation.
- `previous_request_ids` (list of string, optional) — A list of request\_id of the samples that were generated before this generation. Can be used to improve the speech's continuity when splitting up a large task into multiple requests. The results will be best when the same model is used across the generations. In case both previous\_text and previous\_request\_ids is send, previous\_text will be ignored. A maximum of 3 request\_ids can be send.
- `next_request_ids` (list of string, optional) — A list of request\_id of the samples that come after this generation. next\_request\_ids is especially useful for maintaining the speech's continuity when regenerating a sample that has had some audio quality issues. For example, if you have generated 3 speech clips, and you want to improve clip 2, passing the request id of clip 3 as a next\_request\_id (and that of clip 1 as a previous\_request\_id) will help maintain natural flow in the combined speech. The results will be best when the same model is used across the generations. In case both next\_text and next\_request\_ids is send, next\_text will be ignored. A maximum of 3 request\_ids can be send.
- `use_pvc_as_ivc` (boolean, optional, default: false) — Whether to use the IVC version of a professional voice. This may improve expressiveness and reduce latency.
- `apply_text_normalization` (enum, optional, default: auto) — This parameter controls text normalization with three modes: 'auto', 'on', and 'off'. When set to 'auto', the system will automatically decide whether to apply text normalization (e.g., spelling out numbers). With 'on', text normalization will always be applied, while with 'off', it will be skipped.
  - Allowed values: `auto`, `on`, `off`
- `apply_language_text_normalization` (boolean, optional, default: false) — This parameter controls language text normalization. This helps with proper pronunciation of text in some supported languages. WARNING: This parameter can heavily increase the latency of the request. Currently only supported for Japanese.

## Response

**200**

Successful Response

- `audio_base64` (string, required) — Base64 encoded audio data
- `alignment` (CharacterAlignmentResponseModel, optional, nullable) — Timestamp information for each character in the original text
- `normalized_alignment` (CharacterAlignmentResponseModel, optional, nullable) — Timestamp information for each character in the normalized text

## Errors

### 422 Unprocessable Entity Error

Validation Error

- `detail` (list of ValidationError, optional)

**Types**

**VoiceSettingsResponseModel**

- `stability` (double, optional, nullable, default: 0.5) — Determines how stable the voice is and the randomness between each generation. Lower values introduce broader emotional range for the voice. Higher values can result in a monotonous voice with limited emotion.
- `use_speaker_boost` (boolean, optional, nullable, default: true) — This setting boosts the similarity to the original speaker. Using this setting requires a slightly higher computational load, which in turn increases latency.
- `similarity_boost` (double, optional, nullable, default: 0.75) — Determines how closely the AI should adhere to the original voice when attempting to replicate it.
- `style` (double, optional, nullable, default: 0) — Determines the style exaggeration of the voice. This setting attempts to amplify the style of the original speaker. It does consume additional computational resources and might increase latency if set to anything other than 0.
- `speed` (double, optional, nullable, default: 1) — Adjusts the speed of the voice. A value of 1.0 is the default speed, while values less than 1.0 slow down the speech, and values greater than 1.0 speed it up.

**PronunciationDictionaryVersionLocatorRequestModel**

- `pronunciation_dictionary_id` (string, required) — The ID of the pronunciation dictionary.
- `version_id` (string, optional, nullable) — The ID of the version of the pronunciation dictionary. If not provided, the latest version will be used.

**CharacterAlignmentResponseModel**

- `characters` (list of string, required)
- `character_start_times_seconds` (list of double, required)
- `character_end_times_seconds` (list of double, required)

**ValidationError**

- `loc` (list of ValidationErrorLocItems, required)
- `msg` (string, required)
- `type` (string, required)

**ValidationErrorLocItems**

**Examples**

**Request**

```json
{
  "text": "This is a test for the API of ElevenLabs."
}
```

**Response**

```json
{
  "audio_base64": "base64_encoded_audio_string",
  "alignment": {
    "characters": [
      "H",
      "e",
      "l",
      "l",
      "o"
    ],
    "character_start_times_seconds": [
      0,
      0.1,
      0.2,
      0.3,
      0.4
    ],
    "character_end_times_seconds": [
      0.1,
      0.2,
      0.3,
      0.4,
      0.5
    ]
  },
  "normalized_alignment": {
    "characters": [
      "H",
      "e",
      "l",
      "l",
      "o"
    ],
    "character_start_times_seconds": [
      0,
      0.1,
      0.2,
      0.3,
      0.4
    ],
    "character_end_times_seconds": [
      0.1,
      0.2,
      0.3,
      0.4,
      0.5
    ]
  }
}
```

**SDK Code**

```typescript
import { ElevenLabsClient } from "@elevenlabs/elevenlabs-js";

async function main() {
    const client = new ElevenLabsClient();
    await client.textToSpeech.convertWithTimestamps("21m00Tcm4TlvDq8ikWAM", {
        text: "This is a test for the API of ElevenLabs.",
    });
}
main();

```

```python
from elevenlabs import ElevenLabs

client = ElevenLabs()

client.text_to_speech.convert_with_timestamps(
    voice_id="21m00Tcm4TlvDq8ikWAM",
    text="This is a test for the API of ElevenLabs.",
)

```

```go
package main

import (
	"fmt"
	"strings"
	"net/http"
	"io"
)

func main() {

	url := "https://api.elevenlabs.io/v1/text-to-speech/21m00Tcm4TlvDq8ikWAM/with-timestamps"

	payload := strings.NewReader("{\n  \"text\": \"This is a test for the API of ElevenLabs.\"\n}")

	req, _ := http.NewRequest("POST", url, payload)

	req.Header.Add("Content-Type", "application/json")

	res, _ := http.DefaultClient.Do(req)

	defer res.Body.Close()
	body, _ := io.ReadAll(res.Body)

	fmt.Println(res)
	fmt.Println(string(body))

}
```

```ruby
require 'uri'
require 'net/http'

url = URI("https://api.elevenlabs.io/v1/text-to-speech/21m00Tcm4TlvDq8ikWAM/with-timestamps")

http = Net::HTTP.new(url.host, url.port)
http.use_ssl = true

request = Net::HTTP::Post.new(url)
request["Content-Type"] = 'application/json'
request.body = "{\n  \"text\": \"This is a test for the API of ElevenLabs.\"\n}"

response = http.request(request)
puts response.read_body
```

```java
import com.mashape.unirest.http.HttpResponse;
import com.mashape.unirest.http.Unirest;

HttpResponse<String> response = Unirest.post("https://api.elevenlabs.io/v1/text-to-speech/21m00Tcm4TlvDq8ikWAM/with-timestamps")
  .header("Content-Type", "application/json")
  .body("{\n  \"text\": \"This is a test for the API of ElevenLabs.\"\n}")
  .asString();
```

```php
<?php
require_once('vendor/autoload.php');

$client = new \GuzzleHttp\Client();

$response = $client->request('POST', 'https://api.elevenlabs.io/v1/text-to-speech/21m00Tcm4TlvDq8ikWAM/with-timestamps', [
  'body' => '{
  "text": "This is a test for the API of ElevenLabs."
}',
  'headers' => [
    'Content-Type' => 'application/json',
  ],
]);

echo $response->getBody();
```

```csharp
using RestSharp;

var client = new RestClient("https://api.elevenlabs.io/v1/text-to-speech/21m00Tcm4TlvDq8ikWAM/with-timestamps");
var request = new RestRequest(Method.POST);
request.AddHeader("Content-Type", "application/json");
request.AddParameter("application/json", "{\n  \"text\": \"This is a test for the API of ElevenLabs.\"\n}", ParameterType.RequestBody);
IRestResponse response = client.Execute(request);
```

```swift
import Foundation

let headers = ["Content-Type": "application/json"]
let parameters = ["text": "This is a test for the API of ElevenLabs."] as [String : Any]

let postData = JSONSerialization.data(withJSONObject: parameters, options: [])

let request = NSMutableURLRequest(url: NSURL(string: "https://api.elevenlabs.io/v1/text-to-speech/21m00Tcm4TlvDq8ikWAM/with-timestamps")! as URL,
                                        cachePolicy: .useProtocolCachePolicy,
                                    timeoutInterval: 10.0)
request.httpMethod = "POST"
request.allHTTPHeaderFields = headers
request.httpBody = postData as Data

let session = URLSession.shared
let dataTask = session.dataTask(with: request as URLRequest, completionHandler: { (data, response, error) -> Void in
  if (error != nil) {
    print(error as Any)
  } else {
    let httpResponse = response as? HTTPURLResponse
    print(httpResponse)
  }
})

dataTask.resume()
```

## Related pages

- [Administration](./administration-index.md)
- [API reference](./api-reference-index.md)
- [Changelog](./changelog-index.md)
- [ElevenAgents](./elevenagents-index.md)
- [ElevenAPI](./elevenapi-index.md)
- [ElevenCreative](./elevencreative-index.md)
- [ElevenLabs Documentation Docs](../index.md)
- [General Troubleshooting FAQ](./troubleshooting-index.md)
- [General Website FAQ](./website-index.md)
- [Help Center](./help-center-2-index.md)

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