Free tool
Gemini watermark remover
Remove the visible sparkle from images you made with Gemini or Nano Banana. It runs on your own device and works out only the pixels under the mark. The invisible SynthID watermark stays in place.
How to use it
- Drop your Gemini images on the page, paste one, or click to choose them.
- Compare the close-ups of the mark's area, before and after.
- Download images one by one, or click Download all for a ZIP.
Use the original download if you can. An image that has been resized, cropped or screenshotted usually can't be matched, and the tool will tell you instead of guessing.
New images: use Google's own switch
In August 2026 Google announced a setting that turns the visible mark off, at Settings > Media watermark. If you can see it in your account, it's the simplest way to make new images without the sparkle. This tool is for images you've already made.
How it works
The sparkle is a white shape laid over the picture at a known strength, so the original colour of each pixel can be worked out with arithmetic. Most removers paint over the area with AI and guess what was there. This one doesn't guess, and it uses no AI model at all.
It first checks the places where Gemini puts the mark. It only changes the picture if it finds a close match, because subtracting a mark that isn't there would leave a dark star. If it isn't sure, your image is left alone.
What it doesn't remove
SynthID stays. Google says all images made with its models carry this invisible watermark, and this tool doesn't touch it. Gemini can still recognise the picture as AI-made.
Content Credentials stay in PNG and JPEG files. The tool copies this record into the new file, and checkers can see the picture was edited after it was signed. WebP files lose their metadata when saved.
Other watermarks stay. It only knows Gemini's sparkle. It can't remove stock photo marks, logos or text, and it isn't meant to.
Use it honestly
Removing the sparkle doesn't change what the picture is. Don't present an AI image as a real photo or as your own hand-made work, especially news, people or evidence. The rules on labelling AI images differ from country to country and from platform to platform, so check the ones that apply to you. Use this only on images you have the right to edit.
Limits
- Up to 50 images at a time, each up to 60 MB.
- PNG, JPEG and WebP. JPEG and WebP are saved again at high quality, so they change very slightly across the picture. PNG keeps every other pixel exactly.
- A very faint mark can be missed, and a faint trace can remain, so compare the close-ups before you use a file. The tool warns you when it can tell, but it can't always tell.
Frequently asked questions
Something else? contact@getoxtro.com
Is it free?
Yes. There's no account, no credits and no limit beyond your device's memory, because your own device does the work.
Are my images uploaded?
No. They're processed by code running in your browser and never reach our server. If you accept analytics in the cookie banner, we count how many images were processed, but never their names or contents.
Does it remove SynthID?
No. It only removes the visible sparkle. We don't offer SynthID removal.
Will the picture lose quality?
Only the pixels under the mark are recalculated. In a PNG, every other pixel stays exactly the same. JPEG and WebP files are saved again at high quality, as any editor would.
Why did it say no sparkle was found?
Either the image has no mark, or it was resized or cropped so the mark no longer sits where Gemini puts it. Try the original download. Very faint marks can also be missed, because the tool would rather leave your picture alone than damage it.
Can it make the picture bigger too?
Yes, with a separate tool. Remove the sparkle first, then use the Nano Banana upscaler, because enlarging first would make the mark impossible to match.
Is this made by Google?
No. Oxtro isn't affiliated with Google. The mark shapes come from the open-source gemini-watermark-remover project under the MIT licence.
Made by Oxtro
Picture cleaned up. Now put it in front of people.
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