Why big image batches are slow in Flow
For every image set, Flow needs you to paste a prompt, pick the model and aspect ratio, press Generate, wait, then open and download each result. That is fine for five images. For a product catalogue, a thumbnail set or a storyboard it quickly becomes an afternoon of clicking.
A bulk workflow fixes this in three parts: a prompt list, a queue that submits each prompt for you, and auto-download that saves and names every file.
What you need
- Access to Google Flow with your Google account, and enough Flow credits for the batch. Every image is generated in your own account.
- Desktop Google Chrome (version 116 or newer).
- The free AutoPrompt Flow extension, which runs the queue and the downloads.
Step by step
- Write your prompt list. One prompt per block, with an empty line between prompts. Keep the style words the same in every prompt so the set looks consistent.
Studio photo of a matte black water bottle on a light grey background, soft shadow, 85mm lens, catalogue style Studio photo of a sage green water bottle on a light grey background, soft shadow, 85mm lens, catalogue style Studio photo of a coral red water bottle on a light grey background, soft shadow, 85mm lens, catalogue style
- Open Google Flow and the side panel. Go to flow.google.com, open a project, then click the AutoPrompt Flow icon in Chrome's toolbar. The panel shows "Connected to Google Flow".
- Choose Text to Image. In the Mode card, pick Text to Image.
- Pick the model and size. Choose a Nano Banana model (Pro, 2.1 or 2.1 Light), the aspect ratio (square for products, 16:9 for thumbnails, 9:16 for Stories) and how many outputs you want per prompt (x1 to x4). Try two or three prompts with each model first and compare the results and the credits they use.
- Set up auto-download. In Settings → Auto download, choose the image quality (1K is fastest; 2K and 4K are upscaled) and a folder name. In Chrome's own download settings, turn off "Ask where to save each file" so files save without a pop-up.
- Paste the prompts and press Start. Keep the Flow tab open. The queue shows each prompt as it runs, retries failures automatically, and every image lands in
Downloads/your-folder.
#bottle-black and the file is saved as bottle-black.png instead of a numbered name (naming files by tag is a Pro feature).Edit existing images in bulk
To restyle or fix images you already have, use Image to Image. Drop your images into the panel, then either let them be used in order or name each file after a word in its prompt (for example lion.png for a prompt that mentions "lion") and turn on Auto pick by name. With Chain: edit previous image, each prompt edits the result of the one before, which is handy for step-by-step changes.
Tips for better batches
- Test small first. Run three prompts, check the look, then run the rest.
- Keep a style suffix. End every prompt with the same lighting, lens and style words.
- Pace long runs. Leave a few seconds between prompts and run one at a time. Very fast activity can trigger Flow's "unusual activity" warning.
- Mind your credits. Outputs per prompt multiply the cost: 50 prompts at x4 is 200 images.
FAQ
Can Google Flow generate multiple images at once?
Flow can return up to four images per prompt, but you still submit prompts one at a time. To run a whole list, use a queue such as the AutoPrompt Flow extension, which submits each prompt for you and downloads the results.
Which Nano Banana model should I use for bulk images?
Nano Banana Pro is the top model for detail, and the Light model is meant for quick drafts. Run a few prompts with each, compare quality and credit use in your Flow account, then run the full batch with the one you like.
Is bulk image generation on Google Flow free?
The images use your own Google Flow plan and credits. The AutoPrompt Flow extension has a free plan with 20 prompts a day for Text to Image; Pro removes the limit and adds 2K and 4K downloads and Image to Image.