Add a watermark to your photos
Directly in your browser, with no files sent to a server.
Why add a watermark to your photos?
Protect your work and reinforce your visual identity with complete privacy.
Protect your work
Add your brand, logo or text to images before publishing or sending them to a client. Processing happens locally in your browser.
- check_circleDiscourages theft and unauthorized reuse
- check_circleAssert your authorship (Copyright)
- check_circleStrengthen your brand identity
Copyright protection
Complete customization
Your brand, your style
Keep your photos looking natural. Our tool gives you precise controls to integrate your watermark elegantly and professionally.
- check_circleImport a logo (PNG, SVG, JPG) with transparency
- check_circleTiled mode for maximum protection
- check_circleFull font and color picker controls
Process 100 images in one click
Import a whole folder, configure your watermark once, then download everything as a ZIP.
- check_circleLocal processing dans le navigateur
- check_circleZIP export automatique pour les lots
- check_circleGuaranteed privacy: 0 server uploads
Direct export
100% Private
100% processing on your device
Your images never leave your browser. Processing happens entirely on your device — no upload to our servers.
- check_circlePrivacy - Zero transit over the internet
- check_circleDirectly in the browser - Local processing
- check_circleZero risk - No data leakage
Add a watermark to your images
Place text or a logo on your photos directly in the browser, without sending them to a server.
In the browser
Watermark your photos without sending them to a server.
Local processing
Your files stay on your device. No data is sent.
Customizable
Text, logo, tiling, opacity, position… Everything is adjustable.
ZIP export
Download all your watermarked images in one file.
How it works
Add a watermark to your images in three simple steps.
Upload your images
Drag and drop your files, or select them from your device.
Customize the watermark
Text or logo, size, opacity, position… Adjust it as you like.
Download
Download your watermarked images individually or as a ZIP.
Frequently asked questions
Are my images sent to a server?expand_more
No, never. Constelly uses your device's power to process images. Your photos never leave your computer.
Which file formats can I use?expand_more
The tool supports JPG, PNG, WebP, HEIC and HEIF. HEIC/HEIF inputs are exported as JPEG for reliable local watermarking.
Is my photo metadata preserved?expand_more
Yes. JPEG EXIF is preserved; HEIC/HEIF EXIF is reinjected into the exported JPEG. Orientation is normalized to prevent double rotation.
Can I remove a watermark after saving the image?expand_more
No. The watermark is permanently merged into the image; that is the purpose of this protection.
Is image watermarking free?expand_more
Yes, image watermarking is free and requires no sign-up. To process large volumes or use it regularly, switch to Pro.