CleanMark is a free online AI tool whose main purpose is to remove watermarks from images generated by Google Gemini and Nano Banana (Google AI Studio). According to the official description, it can automatically recognize and remove Gemini watermarks and Nano Banana watermark patterns, and the processed images have no watermark and no quality loss.
Main capabilities:
- Automatically detects Gemini watermarks and Nano Banana watermark patterns, which the official description says can reach pixel-level precision.
- Supports JPG, PNG, and WebP image formats, with drag-and-drop or file selection upload.
- Powered by WebAssembly, which the official description says can complete removal in milliseconds.
- Supports custom output dimensions: you can fill in one dimension to auto-scale, or set both dimensions for precise output; that is, you can adjust the size while removing the watermark.
- Provides a Chrome extension.
How to use:
- Open cleanmark.org to use it online, with no installation required.
- Drag and drop or select a watermarked Gemini or AI Studio image.
- CleanMark automatically detects Gemini and Nano Banana watermark patterns.
- The official description says it removes watermarks in milliseconds through reverse alpha blending.
- Download images without watermarks and with zero quality loss.
Privacy and cost:
- All processing is done locally in the browser via JavaScript, and the official description says images do not leave the device and are not uploaded to any server.
- The official description says it is completely free, with no account required, no subscription, no usage limits, no hidden fees, and free forever.
Use cases (as listed officially):
- Content creators: clean up Gemini images for social media, blogs, and newsletters.
- Client work and portfolios: obtain Gemini images without watermarks.
- Academic work and reports: remove watermarks from AI-generated charts and visual assets.
- Presentations and teaching materials: clean up AI-generated images.
Limitations and notes:
- The official focus is mainly on Gemini and Nano Banana (Google AI Studio) watermarks, and it does not state that it can remove watermarks from other platforms.
- Details such as specific browser compatibility, how to install the Chrome extension, and limits on the number and size of processed images are not yet provided.
- Whether batch processing is supported is not yet provided.
- The above features and promises all come from the official page description, and actual results may vary depending on the image.
