nanobanana

Nanobanana

This is a guide for generating and editing images using the nanobanana CLI tool.

Nanobanana is a command-line interface for the Nano Banana image generation API, which uses Google's generative AI models.

Installation

If the nanobanana CLI is not already installed, install it using:

go install maragu.dev/nanobanana@latest

Prerequisites

The GOOGLE_API_KEY environment variable must be set, or a .env file with the key must be present in the working directory.

Generating images

To generate a single image:

nanobanana generate output.png "a beautiful sunset over mountains"

The output can be either a .png or .jpg file.

Using version 2 (preferred)

Always use the -v2 flag unless the user specifically requests the pro model. Version 2 offers improved quality and aspect ratio support:

nanobanana generate -v2 output.png "a beautiful sunset over mountains"

Using the pro model

To use the highest-quality pro model (only when explicitly requested):

nanobanana generate -pro output.png "a beautiful sunset over mountains"

Editing existing images

To edit or modify an existing image using a text prompt:

nanobanana generate -i input.png output.png "make the sky purple and add stars"

This is useful for making specific changes to existing images based on natural language instructions.

Tips for effective prompts

• Be specific and descriptive about what you want in the image
• Include details about style, colors, mood, composition, and subject matter
• For edits, clearly describe what should change while the rest remains the same
• You can reference art styles, artists, or specific visual aesthetics

Examples

Generate a logo:

nanobanana generate logo.png "minimalist tech company logo with geometric shapes in blue and white"

Create concept art:

nanobanana generate concept.png "futuristic city skyline at night with neon lights and flying vehicles, cyberpunk style"

Edit an existing photo:

nanobanana generate -i photo.png enhanced.png "enhance the colors and make it look like golden hour"