next steps in your workflow
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Pro
Skip the manual workflow. One purchase locks in every future watermark layout — in batch.
- batch process up to 100 images at once
- auto-detect any future Gemini watermark layout
- SynthID-aware mode
- Imagen, ChatGPT image, Sora support as added
Refundable until launch. You'll be notified within 14 days when it ships.
how it works
client-side
images never leave your device — all processing happens in the browser
reverse alpha blend
mathematically recovers original pixels using pre-captured alpha maps
auto-detect
detects watermark size (48×48 or 96×96) based on image dimensions
lossless output
saves as png to avoid any additional compression artifacts
example
zoom into the watermark area
frequently asked questions
what is the Gemini watermark?
Google Gemini adds a small semi-transparent 4-point star watermark to AI-generated images. It appears in the bottom-right corner of every image created by Gemini's image generation models. The watermark is 48×48 pixels on smaller images and 96×96 pixels on images larger than 1024×1024.
is this tool safe to use?
Yes. This tool runs entirely in your browser using the Canvas API. Your images are never uploaded to any server — all processing happens locally on your device. You can verify this by checking the network tab in your browser's developer tools while using the tool.
how does the watermark removal work?
The tool uses reverse alpha blending to mathematically recover the original pixel values. The Gemini watermark is applied as a semi-transparent white overlay with a known alpha pattern. By capturing this alpha pattern (the alpha map), we can reverse the blending equation: original = (watermarked - alpha × 255) / (1 - alpha) for each color channel.
what image formats are supported?
You can upload PNG, JPEG, and WebP images. The output is always saved as lossless PNG to avoid introducing any compression artifacts during the watermark removal process.
can I process multiple images at once?
Yes. You can select or drag-and-drop multiple images at once. Each image is processed sequentially and you can download them individually or all at once.
does this remove EXIF metadata too?
Yes. When the image is drawn to the browser's Canvas element for processing, all EXIF and metadata is stripped automatically. The output PNG contains only pixel data.
about this tool
Gemini Nano Banana Watermark Remover is a free, open-source tool that removes the visible star-shaped watermark Google Gemini adds to AI-generated images. Unlike other watermark removal tools that use AI inpainting or blur effects, this tool mathematically reverses the exact blending operation, producing pixel-perfect results with zero quality loss.
The alpha maps used for removal were captured from Gemini's watermark pattern and are included in the tool. The approach is based on work by GargantuaX and allenk.