Gemini Watermark Remover

What it is: An open-source tool that removes the visible Gemini watermark (the semi-transparent logo in the bottom-right corner) from AI-generated images and videos. It works entirely in your browser or on your machine — nothing is uploaded to a server.

How it works

Instead of using AI to guess what's under the watermark (which can hallucinate details), this tool uses a mathematically exact method called Reverse Alpha Blending.

Here's the idea in plain terms:

1. Gemini adds its watermark by blending a white logo over the original image with some transparency level (alpha).
2. The tool knows the exact watermark logo and can figure out the transparency level at each pixel.
3. It then reverses the blending formula to recover the original pixel values — with zero loss.

Detection is layered:

• It first checks the image dimensions against Gemini's known output sizes to predict where the watermark should be.
• Then it scans the actual pixel data around that predicted spot to confirm the exact position.
• Finally, it validates that a real watermark exists before removing anything, to avoid false positives.

Ways to use it

Method	Best for
Online tool (geminiwatermarkremover.io)	Quick, no-install use in the browser
Video remover (geminiwatermarkremover.io/video)	Removing watermarks from Gemini-generated videos
Chrome extension	Automatic integration with Gemini pages — previews, copy, and download actions are processed automatically
Userscript (Tampermonkey/Greasemonkey)	Similar to the extension but for userscript managers; replaces preview images in place and intercepts copy/download
CLI (gwr command)	Scripting, CI, and batch processing on local files
Skill	For AI coding agents that can discover and invoke it
SDK	Advanced/internal integration into your own JavaScript code

Key features

• 100% local processing — your images never leave your device
• Mathematical precision — no AI guessing, reproducible results
• Auto-detection — finds the watermark size and position automatically
• Cross-platform — works in Chrome, Firefox, Safari, Edge, and Node.js
• Video support — handles both images and videos

Limitations

• Only removes Gemini's visible watermark (the semi-transparent bottom-right logo)
• Does not remove invisible/steganographic watermarks (like Google's SynthID)
• Designed for Gemini's current watermark pattern (validated through April 2026)
• Variations in Gemini's watermark implementation or unusual image formats could cause unexpected results

Technical requirements

• Web/userscript: A modern browser with Canvas API, ES modules, and TypedArray support
• CLI/Skill: Node.js, plus the sharp library for file decoding/encoding

License and credits

• Released under the MIT License
• A JavaScript port of Allen Kuo's Gemini Watermark Tool, with the Reverse Alpha Blending method based on his original work

Important warnings

• Use at your own risk — the tool modifies image files and could corrupt them in edge cases
• Legal disclaimer — removing watermarks may have legal implications depending on your jurisdiction and intended use; users are solely responsible for compliance with laws and terms of service
• The author does not condone misuse for copyright infringement or misrepresentation

Quick start (CLI example)

# Remove watermark from an image
gwr remove input.png --output clean.png

# Remove watermark from a video
gwr remove input.mp4 --output clean.mp4