Model ID

gemini-2.5-flash-image

Calling method: sync

Gemini 2.5 Flash Image API Usage Guide

Overview

Gemini 2.5 Flash Image is optimized for image understanding and generation, offering a balance of price and performance. It uses the speed and cost-effectiveness of Gemini 2.5 Flash to provide fast and efficient image generation and editing capabilities. Supports text-to-image, image editing, and multi-turn conversations. Each generated image consumes 1290 tokens. Reference: https://docs.cloud.google.com/vertex-ai/generative-ai/docs/models/gemini/2-5-flash-image

Authentication

All API requests require authentication using an API key. Include your API key in the Authorization header:

Authorization: Bearer YOUR_API_KEY

Submit Image Generation Request

Base URL

https://console.gmicloud.ai

Endpoint

POST /api/v1/ie/requestqueue/apikey/requests

Request Format

curl -X POST "https://console.gmicloud.ai/api/v1/ie/requestqueue/apikey/requests" \
  -H "Authorization: Bearer YOUR_API_KEY" \
  -H "Content-Type: application/json" \
  -d '{
    "model": "gemini-2.5-flash-image",
    "payload": {
      "prompt": "A hyperrealistic portrait of a cyberpunk woman under neon lights",
      "image": [
        "https://example.com/ref1.jpg"
      ],
      "aspect_ratio": "4:5"
    }
  }'

Request Parameters

Parameter	Type	Required	Description	Default	Constraints
`prompt`	string	Yes	Text description of the desired image.	-	Required
`image`	string/array	No	Optional reference image URLs (up to 3). Supported formats: PNG, JPEG, WebP, HEIC, HEIF. Max 7MB inline or 30MB from GCS.	-	Max 3 images
`aspect_ratio`	string	No	Aspect ratio of the generated image.	”1:1”	Options: “1:1”, “3:2”, “2:3”, “3:4”, “4:3”, “4:5”, “5:4”, “9:16”, “16:9”, “21:9”

Response

{
  "request_id": "7eaa77fc-bc67-4021-9f1b-96b3fd832314",
  "model": "gemini-2.5-flash-image",
  "status": "queued",
  "created_at": 1761763441,
  "updated_at": 1761763441,
  "queued_at": 1761763441
}

Check Request Status

Endpoint

GET /api/v1/ie/requestqueue/apikey/requests/{request_id}

Example

curl -X GET "https://console.gmicloud.ai/api/v1/ie/requestqueue/apikey/requests/7eaa77fc-bc67-4021-9f1b-96b3fd832314" \
  -H "Authorization: Bearer YOUR_API_KEY"

Response

{
  "request_id": "7eaa77fc-bc67-4021-9f1b-96b3fd832314",
  "model": "gemini-2.5-flash-image",
  "status": "success",
  "payload": {
    "prompt": "A hyperrealistic portrait of a cyberpunk woman under neon lights",
    "image": [
      "https://example.com/ref1.jpg"
    ],
    "aspect_ratio": "4:5"
  },
  "outcome": {
    "media_urls": [
      {
        "id": "0",
        "url": "https://storage.googleapis.com/gmi-generated-assets/.../gemini_output_0.png"
      }
    ]
  },
  "created_at": 1761763441,
  "updated_at": 1761763451,
  "queued_at": 1761763441
}

Request Status Values

Status	Description
`queued`	Request is waiting to be processed
`processing`	Image generation is in progress
`success`	Image generation completed successfully
`failed`	Image generation failed
`cancelled`	Request was cancelled

List Your Requests

Endpoint

GET api/v1/ie/requestqueue/apikey/requests?model_id=gemini-2.5-flash-image

Example

curl -X GET "https://console.gmicloud.ai/api/v1/ie/requestqueue/apikey/requests?model_id=gemini-2.5-flash-image" \
  -H "Authorization: Bearer YOUR_API_KEY"

Get Model Information

Endpoint

GET /api/v1/ie/requestqueue/apikey/models/gemini-2.5-flash-image

Example

curl -X GET "https://console.gmicloud.ai/api/v1/ie/requestqueue/apikey/models/gemini-2.5-flash-image" \
  -H "Authorization: Bearer YOUR_API_KEY"

List Available Models

Endpoint

GET /api/v1/apikey/models

Example

curl -X GET "https://console.gmicloud.ai/api/v1/apikey/models" \
  -H "Authorization: Bearer YOUR_API_KEY"

Response

{
    "model_ids": [
        "gemini-2.5-flash-image",
        "gemini-3-pro-image-preview",
        "other-model-1"
    ]
}

Multi-turn Conversation (Iterative Image Editing)

This model supports multi-turn conversations for iterative image editing. After generating an image, you can continue refining it by providing additional instructions.

How It Works

First Turn: Send a regular request with prompt (and optional image)
Response: The response includes next_turn_contents - a pre-formatted conversation history
Next Turn: Copy next_turn_contents to your payload’s contents field, then add your new instruction to the last user turn
Repeat: Continue iterating until satisfied

First Turn Request

curl -X POST "https://console.gmicloud.ai/api/v1/ie/requestqueue/apikey/requests" \
  -H "Authorization: Bearer YOUR_API_KEY" \
  -H "Content-Type: application/json" \
  -d '{
    "model": "gemini-2.5-flash-image",
    "payload": {
      "prompt": "A panda making latte art in a cozy cafe",
      "aspect_ratio": "1:1"
    }
  }'

First Turn Response (with next_turn_contents)

{
  "request_id": "abc123",
  "status": "success",
  "outcome": {
    "media_urls": [{"id": "0", "url": "https://storage.googleapis.com/.../generated.png"}],
    "next_turn_contents": [
      {
        "role": "user",
        "parts": [{"text": "A panda making latte art in a cozy cafe"}]
      },
      {
        "role": "model",
        "parts": [
          {"text": "Here is the generated image."},
          {"fileData": {"mimeType": "image/png", "fileUri": "gs://bucket/generated.png"}}
        ]
      },
      {
        "role": "user",
        "parts": [{"text": ""}, {"fileData": {"mimeType": "image/png", "fileUri": ""}}]
      }
    ]
  }
}

Second Turn Request (Using next_turn_contents)

Copy next_turn_contents to contents, then fill in the last user turn with your new instruction:

curl -X POST "https://console.gmicloud.ai/api/v1/ie/requestqueue/apikey/requests" \
  -H "Authorization: Bearer YOUR_API_KEY" \
  -H "Content-Type: application/json" \
  -d '{
    "model": "gemini-2.5-flash-image",
    "payload": {
      "contents": [
        {
          "role": "user",
          "parts": [{"text": "A panda making latte art in a cozy cafe"}]
        },
        {
          "role": "model",
          "parts": [
            {"text": "Here is the generated image."},
            {"fileData": {"mimeType": "image/png", "fileUri": "gs://bucket/generated.png"}}
          ]
        },
        {
          "role": "user",
          "parts": [{"text": "Change the panda to a brown bear and make the cup blue"}]
        }
      ],
      "aspect_ratio": "1:1"
    }
  }'

Multi-turn Tips

Text-only edits: Just fill in the text field in the last user turn
Add reference image: Include a fileData with fileUri pointing to a GCS or HTTP URL
Empty fields are ignored: Empty text or fileUri are automatically filtered out
Conversation history: Each response includes updated next_turn_contents for the next iteration

Model Specifications

Specification	Value
Model ID	gemini-2.5-flash-image
Max input tokens	32,768
Max output tokens	32,768
Max input images	3
Max output images per prompt	10
Tokens per output image	1,290
Supported image types	PNG, JPEG, WebP, HEIC, HEIF
Max file size (inline)	7 MB
Max file size (GCS)	30 MB
Temperature	0.0–2.0 (default 1.0)
topP	0.0–1.0 (default 0.95)
topK	64 (fixed)

Pricing

Input (text, image, video): $0.30 per 1M tokens
Image output: $30 per 1M tokens (1290 tokens per image ≈ **$ 0.0387 per image**)
Text output: $2.50 per 1M tokens

Tips for Better Results

Prompt Clarity: Use detailed, specific prompts for precise results.
Multi-turn Iteration: For complex edits, use multi-turn mode to refine the image step by step.
Reference Images: Provide up to 3 reference images to guide style and composition.

Overview

Model Quickstarts

Agents

Coding Tools

AgentBox Guides

Migration Guides

gemini-2.5-flash-image

Gemini 2.5 Flash Image API Usage Guide

Overview

Authentication

Submit Image Generation Request

Base URL

Endpoint

Request Format

Request Parameters

Response

Check Request Status

Endpoint

Example

Response

Request Status Values

List Your Requests

Endpoint

Example

Get Model Information

Endpoint

Example

List Available Models

Endpoint

Example

Response

Multi-turn Conversation (Iterative Image Editing)

How It Works

First Turn Request

First Turn Response (with next_turn_contents)

Second Turn Request (Using next_turn_contents)

Multi-turn Tips

Model Specifications

Pricing

Tips for Better Results

​Gemini 2.5 Flash Image API Usage Guide

​Overview

​Authentication

​Submit Image Generation Request

​Base URL

​Endpoint

​Request Format

​Request Parameters

​Response

​Check Request Status

​Endpoint

​Example

​Response

​Request Status Values

​List Your Requests

​Endpoint

​Example

​Get Model Information

​Endpoint

​Example

​List Available Models

​Endpoint

​Example

​Response

​Multi-turn Conversation (Iterative Image Editing)

​How It Works

​First Turn Request

​First Turn Response (with next_turn_contents)

​Second Turn Request (Using next_turn_contents)

​Multi-turn Tips

​Model Specifications

​Pricing

​Tips for Better Results

Gemini 2.5 Flash Image API Usage Guide

Overview

Authentication

Submit Image Generation Request

Base URL

Endpoint

Request Format

Request Parameters

Response

Check Request Status

Endpoint

Example

Response

Request Status Values

List Your Requests

Endpoint

Example

Get Model Information

Endpoint

Example

List Available Models

Endpoint

Example

Response

Multi-turn Conversation (Iterative Image Editing)

How It Works

First Turn Request

First Turn Response (with next_turn_contents)

Second Turn Request (Using next_turn_contents)

Multi-turn Tips

Model Specifications

Pricing

Tips for Better Results