Skip to main content
POST
Use this route to edit GPT images with multipart uploads on RunBridge AI.

Use this route when

  • You already have a source image and want a prompt-driven edit
  • You may need a mask for targeted changes
  • You can handle multipart file upload instead of a plain JSON request

Safe first request

  • Start with one PNG or JPG file
  • Skip the mask until the base edit flow works
  • Use model: "gpt-image-2" for GPT image edit requests on this route
  • Use one short instruction that asks for one visible change
  • Read the edited result from data[0].b64_json
  • Set output_format: "jpeg" when you want a JPEG payload
  • Expect longer latency than plain image generation

Model behavior

  • GPT image edit models on this route return inline base64 image data
  • output_format controls the encoded image type inside b64_json

Authorizations

Authorization
string
header
required

Bearer token authentication. Use your RunBridge AI key.

Body

multipart/form-data
image
file
required

Source image file. Start with one PNG or JPG input for the simplest flow.

prompt
string
required

Edit instruction describing the change you want.

Example:

"Add a small red bow tie on the cat"

model
string
default:gpt-image-2

The GPT image editing model ID. Find model IDs on the Models page.

mask
file

Optional PNG mask. Transparent areas mark the regions to edit. The mask dimensions must match the source image exactly.

n
string
default:1

Number of edited images to return.

quality
enum<string>

Quality setting for models that support it.

Available options:
high,
medium,
low
Example:

"low"

output_format
string

Encoded image type for GPT image edit results returned in data[].b64_json. For example, use jpeg for a JPEG payload.

size
string

Requested output size when supported by the selected model.

Response

200 - application/json

Edited image result.

created
integer
required
usage
object
required
data
object[]
required
background
string

Background mode returned by models that expose it.

output_format
string

Encoded image type returned by GPT image models.

quality
string

Quality level returned by models that expose it.

size
string

Output size returned by models that expose it.

Last modified on October 9, 2026