Gemini Watermark Remover
Drop images made with Gemini and the sparkle in the bottom right corner is found and taken out. The work happens in your browser, so the pictures are not uploaded anywhere.
Why use this gemini watermark remover
Your pictures stay on your device
Detection and removal run in your browser. There is no upload step, no queue and no copy of your image on a server, so private or unreleased work is safe to use.
Calculates the pixels back instead of guessing them
The Gemini star is a known overlay. Reversing its blend restores the original pixel values under the star, so there is no smeared patch where the logo was. Tools that only paint over the area have to invent that detail.
Checks its own result
After the first pass the tool measures what is left of the star and repeats with a better fit when a trace remains, instead of handing you a result it never looked at.
Handles both star sizes
Some Gemini images carry more than one star. Each known position and size is tested, and every star that is found is removed.
No account, no credits, no mark on the output
There is no sign-up, daily limit or watermark added to your download. Clean up to 30 images at a time and save them as one ZIP.
| This tool | Typical online remover | |
|---|---|---|
| Where your image goes | Stays in your browser | Often uploaded to a server |
| How the mark is removed | Reverse blend of the known star, fill only as a fallback | Often painting or inpainting over the area |
| Account or credits | None | Often a sign-up or daily limit |
| Batch | Up to 30 images, one ZIP | Varies |
| Fix a miss by hand | Draw a box and run again | Varies |
Where it is weaker: The fallback fill is simpler than server-side AI inpainting, so on heavily textured backgrounds a hand-selected area can look smoother than its surroundings. Detection is also built only for the Gemini star.
How to use the gemini watermark remover
- Add one or more PNG, JPG or WebP images made with Gemini. Drop them, click the box or select several at once.
- Each image is checked for the sparkle mark and cleaned automatically. The selected one is shown with a before and after slider.
- If the mark was not found or a faint trace is left, press Select the area by hand, draw a box around the star and run it again.
- Download the PNG, or download all finished images as one ZIP.
How it works
Step one: the exact reverse blend
The Gemini mark is a white star drawn over the picture with a fixed opacity pattern. When the position, size and pattern are known, the original pixel can be calculated back from the marked one: original = (marked - alpha x 255) / (1 - alpha). The tool finds where the star sits by matching it against reference captures and applies this to the pixels under the star only. The rest of the picture is not changed.
Step two: check what is left
After the first pass the tool measures how much of the star's shape is still visible. If a trace is left it repeats with a slightly different fit, up to four passes.
Step three: local fill, only when needed
If the mark does not match a known layout (for example the picture was resized or compressed hard), the box around the star is filled from the pixels around it, with matching grain. This also runs in your browser. It works well on smooth or gradual backgrounds and shows on detailed textures, which is why the exact blend is always tried first.
At a glance
| Input | PNG, JPG, WebP |
|---|---|
| Output | PNG (lossless) |
| Batch | Up to 30 images, ZIP download |
| Where it runs | Your browser; no upload, no account |
| Method | Reverse alpha blend, then local fill if a trace remains |
Limits you should know about
- Large images take longer: a 4000 by 4000 picture needs a few seconds. The limit is 40 MB per file and 30 files at a time.
- Output is always PNG, so the result is lossless but can be larger than a JPG input.
- Detection is tuned for the star used on Gemini generated images. Other logos, text overlays and watermarks from other tools are not recognised, though the hand selection will still fill an area you choose.
- Images that were resized or recompressed after download move or soften the star. The tool searches for it, but a result can need a manual selection.
Use it responsibly
- This tool removes the visible mark only. Invisible provenance data, such as SynthID or content credentials, is not touched and may still identify the file as AI generated.
- Do not present AI generated work as human made or as footage of a real event. Check the terms of the service that made the file and your rights to the content before you share or sell it.
- CalcMaster is not affiliated with Google, Gemini, Veo or NotebookLM. The names are used only to say which marks the tool is built for.
Questions
Are my images uploaded?
No. Detection and removal run on your device. The only requests are for the page itself and for the small reference images used to find the mark.
Why is the result sometimes not perfect?
The exact blend is only exact when the star's position and size match what the tool expects. On resized or heavily compressed images a faint trace can remain. Select the area by hand and run it again, or start from the original download.
Does this remove SynthID?
No. SynthID and similar invisible markers are not touched. Only the visible sparkle is removed.
Is it free?
Yes. There is no limit on how many images you clean other than your device's memory.
Which formats can I save?
PNG. If you need JPG or WebP afterwards, use the image converter on this site; it also runs in your browser.
Other watermark tools
- Gemini Video Watermark RemoverRemove the Gemini Veo watermark from MP4, WebM and MOV clips in your browser. Frame by frame reverse blend, audio kept, nothing uploaded. Needs desktop Chrome or Edge.
- NotebookLM Watermark RemoverRemove the NotebookLM badge from PNG, JPG and PDF exports in your browser. Smart gradient fill, batch ZIP, no upload. Not affiliated with Google.
Need another file type afterwards? Try the image converter or the image resizer.
Open source credits
These tools are built on the work of others. Licence notices are kept as the licences require.
| Project | By | Licence | Used for |
|---|---|---|---|
| gemini-watermark-remover | GargantuaX, based on work by Jad and AllenK (Kwyshell) | MIT | Calibrated alpha maps and the reverse blend method for the Gemini mark |
| mediabunny | Vanilagy | MPL-2.0 | Video decoding and encoding with WebCodecs |
| pdf.js | Mozilla | Apache-2.0 | Drawing PDF pages |
| pdf-lib | Andrew Dillon | MIT | Building the cleaned PDF |
| JSZip | Stuart Knightley | MIT or GPL-3.0 | ZIP downloads |