Free local prompt builder

Build a better Nano Banana prompt before you spend credits

Turn a rough idea into a clear image brief that separates the requested change, protected details, composition, lighting, and failure constraints. Nothing is sent to an AI model until you choose to open the paid editor.

Runs in your browserNo sign-up requiredUses zero generation credits

Step 1

Choose a job and edit the brief

No AI call

Step 2

Your structured prompt

Open in editor

Recommended starting point

Nano Banana 2 · 2K · 12 credits

About $0.34–$0.59 with a one-time credit pack.

Building and copying this prompt is free. Credits are used only if you continue to image generation.

Why this format reduces wasted generations

Strong image-editing prompts behave like a small creative brief. They narrow the model's freedom where mistakes are expensive and leave flexibility only where you want it.

Name one primary change

A specific edit is easier to judge and refine than a vague request to improve the whole image.

Lock the valuable details

Identity, product shape, logos, clothing, text, camera angle, and colors should be named explicitly when they matter.

Prevent predictable failures

An avoid list reduces extra people, altered faces, invented text, fake logos, warped anatomy, and unwanted redesigns.

Image generation is paid

Inspect the cost before you continue

The editor carries this prompt into the recommended model and shows the exact credit charge and approximate one-time-pack cost before generation.

See credit packs