Image Watermark Generator
Add custom text or logo watermarks to your photos with opacity and positioning controls.
How to Use
Upload Photo
Select main photo file.
Configure Watermark
Enter text or logo image and set opacity slider.
In-browser Composite
Render watermark overlay onto HTML5 Canvas.
Download
Save watermarked photo directly to your local drive.
Protect Photos with Custom Text & Logo Watermarks
Prevent unauthorized copying of your photography, portfolio images, and commercial graphics. Our Image Watermark Generator lets you overlay semi-transparent text copyright notices or logo images onto your photos with full opacity, font size, and positioning controls.
Watermark your photos 100% privately in your browser tab without uploading master images to remote servers.
Real-World Examples & Use Cases
Professional Photography Portfolio Protection
Add discreet copyright watermarks to preview photos before sharing client proofs or posting on social media.
Real Estate & Property Listing Protection
Add agency logos or website URLs to real estate photos to prevent competitor stealing.
E-Commerce Product Image Copyright
Protect original product photography from unauthorized dropshipper copying.
Confidential Document Marking
Stamp "CONFIDENTIAL" or "DRAFT" watermarks onto sensitive document scans offline.
How It Works
Canvas Alpha Overlay Composition: 1. Master Canvas Draw: ctx.drawImage(masterPhoto, 0, 0). 2. Opacity Setting: ctx.globalAlpha = opacitySliderValue ($0.1$ to $1.0$). 3. Text / Logo Overlay: ctx.font = 'bold 36px Inter'; ctx.fillStyle = '#FFFFFF'; ctx.fillText(watermarkText, posX, posY);
Frequently Asked Questions
Can I control the watermark transparency?▼
Are my un-watermarked master photos uploaded to a server?▼
Can I upload a PNG logo to use as a watermark?▼
Does watermarking reduce photo resolution?▼
Is this tool free to use?▼
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