curl -X POST 'https://api.openai.com/v1/videos/extensions' \
  -H "Authorization: Bearer $OPENAI_API_KEY" \
  -H 'Content-Type: application/json' \
  -d '{
  "video": {
    "id": "video_123"
  },
  "prompt": "example-prompt",
  "seconds": "4"
}'

# POST /videos/extensions (OpenAI API)
Base URL: https://api.openai.com/v1
Auth: Authorization; OpenAI API key; required.
Status: Deprecated.
Request formats: application/json, multipart/form-data.
Last verified: 2026-10-20

> Create a video extension

## Critical Gotchas
* The Responses API is the primary interface for new text and tool workflows; Chat Completions remains a separate compatibility API.
* Audio transcription uploads use multipart form data rather than a JSON request body.

## cURL
curl -X POST 'https://api.openai.com/v1/videos/extensions' \
  -H "Authorization: Bearer $OPENAI_API_KEY" \
  -H 'Content-Type: application/json' \
  -d '{
  "video": {
    "id": "video_123"
  },
  "prompt": "example-prompt",
  "seconds": "4"
}'

## Parameters
| Name | In | Type | Required | Description |
| :--- | :--- | :--- | :--- | :--- |
| video | body | object | Yes | Reference to the completed video. |
| prompt | body | string | Yes | Updated text prompt that directs the extension generation. |
| seconds | body | string | Yes | Request body field seconds. |

## Response example
{"id":"string","object":"video"}

---
Need an API key? Get one at https://platform.openai.com/api-keys

POST

POST /videos/extensions — OpenAI API

Deprecated

OpenAI API key (required); https://api.openai.com/v1

OpenAI API

Create a video extension

Base URL: https://api.openai.com/v1
Auth: Authorization: Bearer <OPENAI_API_KEY>
Last verified: 2026-10-20 · upstream hash matched

Actions Try in browser→

Agents: curl -H "Accept: text/markdown" this URL
→ 232 tokens · Vary: Accept

Critical gotchas

The Responses API is the primary interface for new text and tool workflows; Chat Completions remains a separate compatibility API.

Audio transcription uploads use multipart form data rather than a JSON request body.

cURL

curl -X POST 'https://api.openai.com/v1/videos/extensions' \  -H "Authorization: Bearer $OPENAI_API_KEY" \  -H 'Content-Type: application/json' \  -d '{  "video": {    "id": "video_123"  },  "prompt": "example-prompt",  "seconds": "4"}'

Parameters

Name	In	Type	Required	Description
video	body	object	Yes	Reference to the completed video.
prompt	body	string	Yes	Updated text prompt that directs the extension generation.
seconds	body	string	Yes	Request body field seconds.

Response 200 OK

{
  "id": "string",
  "object": "video",
  "model": "string",
  "status": "queued",
  "progress": 0,
  "created_at": 0,
  "completed_at": 0,
  "expires_at": 0,
  "prompt": "string",
  "size": "720x1280",
  "seconds": "string",
  "remixed_from_video_id": "string",
  "error": {
    "code": "string",
    "type": "string",
    "param": "string",
    "message": "string",
    "headers": {},
    "misalignment": {
      "review_target": "string",
      "error_type": "string",
      "detailed_explanation": "string",
      "steer": {
        "message": "string"
      }
    }
  }
}

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