> ## Documentation Index > Fetch the complete documentation index at: https://apidoc.cometapi.com/llms.txt > Use this file to discover all available pages before exploring further. # Expand an image with Kling > Use Kling Image Expansion API via CometAPI to expand images beyond their original borders with controllable outpainting. Use this endpoint to outpaint an image beyond its original borders when you need more canvas around the source content. ## How the expansion ratios work * Each ratio is measured against the original width or height * The combined expanded canvas must still stay within Kling's documented area limits * Start with small values such as `0.1` on each side before attempting larger expansions ## Request flow * Send all four ratio fields, using `0` for any side you do not want to expand * Save the returned `task_id` * Poll the matching Kling image query path until the task reaches a terminal state For the complete parameter reference, see the [official Kling documentation](https://kling.ai/document-api/api/image/common/outpainting). ## OpenAPI ````yaml api/openapi/image/kling/post-image-expansion.openapi.json POST /kling/v1/images/editing/expand openapi: 3.1.0 info: title: Kling Image Expansion API version: 1.0.0 servers: - url: https://api.cometapi.com security: - bearerAuth: [] paths: /kling/v1/images/editing/expand: post: summary: Expand an image with Kling operationId: kling_image_expansion parameters: - name: Content-Type in: header required: false description: Must be `application/json`. schema: type: string default: application/json requestBody: required: true content: application/json: schema: type: object required: - image - up_expansion_ratio - down_expansion_ratio - left_expansion_ratio - right_expansion_ratio properties: image: type: string description: >- Source image to expand. Image URL or raw Base64 string without a `data:` prefix. Supported formats: JPG, JPEG, PNG. Maximum 10 MB, minimum 300x300 px, aspect ratio between 1:2.5 and 2.5:1. up_expansion_ratio: type: number description: >- Upward expansion ratio as a multiple of the original image dimension. Range: 0-2. Send `0` for sides you do not want to expand. minimum: 0 maximum: 2 down_expansion_ratio: type: number description: >- Downward expansion ratio as a multiple of the original image dimension. Range: 0-2. Send `0` for sides you do not want to expand. minimum: 0 maximum: 2 left_expansion_ratio: type: number description: >- Leftward expansion ratio as a multiple of the original image dimension. Range: 0-2. Send `0` for sides you do not want to expand. minimum: 0 maximum: 2 right_expansion_ratio: type: number description: >- Rightward expansion ratio as a multiple of the original image dimension. Range: 0-2. Send `0` for sides you do not want to expand. minimum: 0 maximum: 2 prompt: type: string description: >- Optional text prompt to guide the expanded area content. Maximum 2500 characters. 'n': type: integer description: 'Number of expanded images to generate. Range: 1-9.' minimum: 1 maximum: 9 default: 1 watermark_info: type: object description: Watermark options. properties: enabled: type: boolean callback_url: type: string description: Webhook URL for task status notifications. external_task_id: type: string description: >- Optional user-defined task ID for your own tracking. Must be unique per account. default: image: https://your-image-host/source.jpg up_expansion_ratio: 0.1 down_expansion_ratio: 0.1 left_expansion_ratio: 0.1 right_expansion_ratio: 0.1 prompt: extend the soft studio background 'n': 1 examples: Default: summary: Expand an image on all four sides value: image: https://your-image-host/source.jpg up_expansion_ratio: 0.1 down_expansion_ratio: 0.1 left_expansion_ratio: 0.1 right_expansion_ratio: 0.1 prompt: extend the soft studio background 'n': 1 responses: '200': description: Task request accepted or an error response returned by the API. content: application/json: schema: type: object required: - code - message - data properties: code: oneOf: - type: integer - type: string description: Response code. `0` means the task request was accepted. message: type: string description: Response message. request_id: type: string description: Request identifier returned when present. data: type: object required: - task_id - task_status - created_at - updated_at properties: task_id: type: string description: System-generated task ID. task_status: type: string description: Task status. enum: - submitted - processing - succeed - failed task_status_msg: oneOf: - type: string - type: 'null' description: Task status detail when present. task_info: type: object properties: external_task_id: oneOf: - type: string - type: 'null' description: Caller-provided external task ID when supplied. additionalProperties: true task_result: oneOf: - type: object additionalProperties: true - type: 'null' description: Task result payload after the task completes. created_at: type: integer description: >- Task creation time as a Unix timestamp in milliseconds. updated_at: type: integer description: Task update time as a Unix timestamp in milliseconds. additionalProperties: true additionalProperties: true x-codeSamples: - lang: Shell label: Default source: | curl https://api.cometapi.com/kling/v1/images/editing/expand \ -H "Authorization: Bearer $COMETAPI_KEY" \ -H "Content-Type: application/json" \ -d '{ "image": "https://your-image-host/source.jpg", "up_expansion_ratio": 0.1, "down_expansion_ratio": 0.1, "left_expansion_ratio": 0.1, "right_expansion_ratio": 0.1, "prompt": "extend the soft studio background", "n": 1 }' - lang: Python label: Default source: | import os import requests response = requests.post( "https://api.cometapi.com/kling/v1/images/editing/expand", headers={"Authorization": "Bearer " + os.environ["COMETAPI_KEY"]}, json={ "image": "https://your-image-host/source.jpg", "up_expansion_ratio": 0.1, "down_expansion_ratio": 0.1, "left_expansion_ratio": 0.1, "right_expansion_ratio": 0.1, "prompt": "extend the soft studio background", "n": 1 }, ) result = response.json() print(result["code"], result.get("data", {}).get("task_id")) - lang: JavaScript label: Default source: > const response = await fetch("https://api.cometapi.com/kling/v1/images/editing/expand", { method: "POST", headers: { Authorization: `Bearer ${process.env.COMETAPI_KEY}`, "Content-Type": "application/json", }, body: JSON.stringify({ "image": "https://your-image-host/source.jpg", "up_expansion_ratio": 0.1, "down_expansion_ratio": 0.1, "left_expansion_ratio": 0.1, "right_expansion_ratio": 0.1, "prompt": "extend the soft studio background", "n": 1 }), }); const result = await response.json(); console.log(result.code, result.data?.task_id); components: securitySchemes: bearerAuth: type: http scheme: bearer description: Bearer token authentication. Use your CometAPI key. ````