---
title: "Expand an image with FLUX.1 Expand [pro] by adding pixels on any side"
method: POST
path: "/v1/flux-pro-1.0-expand"
tags: ["Models"]
---

# Expand an image with FLUX.1 Expand [pro] by adding pixels on any side

`POST /v1/flux-pro-1.0-expand`

Submits an image expansion task that adds the specified number of pixels to any combination of sides (top, bottom, left, right) while maintaining context.

## Request body

- FluxProExpandInputs
  - `image` string, required — A Base64-encoded string representing the image you wish to expand.
  - `top` integer, nullable — Number of pixels to expand at the top of the image
  - `bottom` integer, nullable — Number of pixels to expand at the bottom of the image
  - `left` integer, nullable — Number of pixels to expand on the left side of the image
  - `right` integer, nullable — Number of pixels to expand on the right side of the image
  - `prompt` string, nullable — The description of the changes you want to make. This text guides the expansion process, allowing you to specify features, styles, or modifications for the expanded areas.
  - `steps` integer, nullable — Number of steps for the image generation process
  - `prompt_upsampling` boolean, nullable — Whether to perform upsampling on the prompt. If active, automatically modifies the prompt for more creative generation
  - `seed` integer, nullable — Optional seed for reproducibility
  - `guidance` number, nullable — Guidance strength for the image generation process
  - `output_format` 'jpeg' | 'png' | 'webp'
  - `safety_tolerance` integer — Tolerance level for input and output moderation. Between 0 and 6, 0 being most strict, 6 being least strict.
  - `webhook_url` string, uri, nullable — URL to receive webhook notifications
  - `webhook_secret` string, nullable — Optional secret for webhook signature verification

## Response `200`

Successful Response

- union
  - AsyncResponse
    - `id` string, required
    - `polling_url` string, required
    - `cost` number, nullable — Cost in credits for this request
    - `input_mp` number, nullable — Input megapixels (2 decimal places)
    - `output_mp` number, nullable — Output megapixels (2 decimal places)
  - AsyncWebhookResponse
    - `id` string, required
    - `status` string, required
    - `webhook_url` string, required
    - `cost` number, nullable — Cost in credits for this request
    - `input_mp` number, nullable — Input megapixels (2 decimal places)
    - `output_mp` number, nullable — Output megapixels (2 decimal places)

## Other responses

- `422` — Validation Error

---

[API](https://skmtc.net/bfl/apis/bfl-api.md) · [All operations](https://skmtc.net/bfl/apis/bfl-api/llms.txt) · [OpenAPI document](https://skmtc-service-staging.skmtc.workers.dev/v1/apis/bfl/bfl-api/versions/a0209bab18e1/schema)