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# Start/Update a video translation

PUT https://api.synthesia.io/v2/translations/{root_video_id}
Content-Type: application/json

Kick off TranslateVideoWorkflow for each requested target language. Returns a unified `translations` list. Each entry includes a `startedByRequest` flag: `true` if the workflow was started by this request, `false` if it was already in progress.

Reference: https://developers.synthesia.io/docs/video-api-reference/translations/start-update-a-video-translation

## Authentication

- `Authorization` header (required) — API Key authentication via header

## Request

### Path parameters

- `root_video_id` (string, required) — The ID of the studio video to translate.

### Body (application/json)

This endpoint expects an UpsertVideoTranslationsApiRequest.

- `targetLanguages` (list of string, required) — List of language codes to translate the video into. See https://docs.synthesia.io/docs/supported-languages for accepted values.
- `translateScriptOnly` (boolean, optional, default: false) — If true, only the script is translated.
- `autoGenerate` (enum, optional, nullable) — Automatically generate the translated video after translation completes. Set to 'private' to generate without sharing publicly, or 'public' to generate and publish immediately.
  - Allowed values: `private`, `public`

## Response

### 202

Accepted – translation workflows started (or already running).

- `id` (string, required) — The ID of the studio video to translate.
- `translations` (list of UpsertVideoTranslationsRunningWorkflowApiItem, required) — List of translations that were created or updated.

## Errors

### 400 Bad Request Error

Bad Request – validation failed (unsupported language, wrong video type, translations not available for this workspace plan, or incompatible options).

- `error` (string, required)
- `context` (string, optional)

### 403 Forbidden Error

Forbidden – wrong API key or user lacks edit permission for the video.

- `error` (string, required)
- `context` (string, optional)

### 404 Not Found Error

Not Found – video not found or Translations API disabled.

- `error` (string, required)
- `context` (string, optional)

## Types

### UpsertVideoTranslationsRunningWorkflowApiItem

- `language` (string, required)
- `step` (enum, required)
  - Allowed values: `translation`
- `status` (enum, optional, default: in_progress)
  - Allowed values: `in_progress`
- `startedByRequest` (boolean, optional, default: true) — Whether the translation was started by the request.

## Examples

**Request**

```json
{
  "targetLanguages": [
    "es",
    "fr"
  ]
}
```

**Response**

```json
{
  "id": "string",
  "translations": [
    {
      "language": "fr",
      "step": "translation",
      "status": "in_progress"
    }
  ]
}
```

**SDK Code**

```python
import requests

url = "https://api.synthesia.io/v2/translations/root_video_id"

payload = { "targetLanguages": ["es", "fr"] }
headers = {
    "Authorization": "<apiKey>",
    "Content-Type": "application/json"
}

response = requests.put(url, json=payload, headers=headers)

print(response.json())
```

```javascript
const url = 'https://api.synthesia.io/v2/translations/root_video_id';
const options = {
  method: 'PUT',
  headers: {Authorization: '<apiKey>', 'Content-Type': 'application/json'},
  body: '{"targetLanguages":["es","fr"]}'
};

try {
  const response = await fetch(url, options);
  const data = await response.json();
  console.log(data);
} catch (error) {
  console.error(error);
}
```

```go
package main

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

func main() {

	url := "https://api.synthesia.io/v2/translations/root_video_id"

	payload := strings.NewReader("{\n  \"targetLanguages\": [\n    \"es\",\n    \"fr\"\n  ]\n}")

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

	req.Header.Add("Authorization", "<apiKey>")
	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.synthesia.io/v2/translations/root_video_id")

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

request = Net::HTTP::Put.new(url)
request["Authorization"] = '<apiKey>'
request["Content-Type"] = 'application/json'
request.body = "{\n  \"targetLanguages\": [\n    \"es\",\n    \"fr\"\n  ]\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.put("https://api.synthesia.io/v2/translations/root_video_id")
  .header("Authorization", "<apiKey>")
  .header("Content-Type", "application/json")
  .body("{\n  \"targetLanguages\": [\n    \"es\",\n    \"fr\"\n  ]\n}")
  .asString();
```

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

$client = new \GuzzleHttp\Client();

$response = $client->request('PUT', 'https://api.synthesia.io/v2/translations/root_video_id', [
  'body' => '{
  "targetLanguages": [
    "es",
    "fr"
  ]
}',
  'headers' => [
    'Authorization' => '<apiKey>',
    'Content-Type' => 'application/json',
  ],
]);

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

```csharp
using RestSharp;

var client = new RestClient("https://api.synthesia.io/v2/translations/root_video_id");
var request = new RestRequest(Method.PUT);
request.AddHeader("Authorization", "<apiKey>");
request.AddHeader("Content-Type", "application/json");
request.AddParameter("application/json", "{\n  \"targetLanguages\": [\n    \"es\",\n    \"fr\"\n  ]\n}", ParameterType.RequestBody);
IRestResponse response = client.Execute(request);
```

```swift
import Foundation

let headers = [
  "Authorization": "<apiKey>",
  "Content-Type": "application/json"
]
let parameters = ["targetLanguages": ["es", "fr"]] as [String : Any]

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

let request = NSMutableURLRequest(url: NSURL(string: "https://api.synthesia.io/v2/translations/root_video_id")! as URL,
                                        cachePolicy: .useProtocolCachePolicy,
                                    timeoutInterval: 10.0)
request.httpMethod = "PUT"
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()
```