Image Watermark Tool — Add Text & Logo Watermarks to Photos Online — Core Format
FREE BATCH UTILITY
Batch Image Watermark Tool
Protect your visual content and brand your photography in seconds. Add custom text or your company logo across multiple JPG, PNG, and WebP images with 9-point positioning, full-bleed tiling, adjustable opacity, and real-time live preview — 100% private in your browser.
Drag & drop images to watermark
JPG, PNG, or WebP (Batch processing up to 50 photos)
✓ 100% Client-Side Privacy: Your images never leave your browser.
How to Watermark Images in Bulk (4 Easy Steps)
- Upload your photos: Drop JPG, PNG, or WebP files into the upload box. You can watermark a single picture or dozens of images simultaneously.
- Choose text or logo watermark: Type your copyright notice, signature, or handle, or upload a transparent PNG logo.
- Position & customize: Select any of the 9 anchor positions or turn on diagonal tiling. Adjust font family, size, color, opacity, and rotation with the live preview canvas.
- Export & download: Click Apply to All & Download ZIP to watermark all images at full resolution and package them into a single archive, or download images individually.
Why Watermark Your Images?
In the era of social media sharing, AI scrapers, and digital marketplaces, unprotected photography and creative designs are vulnerable to unauthorized reuse, content scraping, and copyright infringement. Watermarking adds a visible attribution mark that reinforces brand identity, discourages unauthorized republishing, and ensures viewers can trace images back to their original creator.
Key Capabilities of CoreFormat Batch Watermark
- Proportional Resolution Scaling: Unlike basic tools that use fixed pixel fonts, CoreFormat scales text and logo sizes proportionally to each photo's native dimensions. A 4K camera snapshot receives the exact same visual watermark proportion as an 800-pixel web thumbnail.
- 9-Point Anchor Matrix & Edge Inset: Place watermarks neatly into corners, centered on borders, or dead-center with configurable edge margins so important subjects are never obscured.
- Full-Bleed Diagonal Tiling: Protect stock photography proofs and commercial mockups with repeating diagonal watermark grids that cover the entire image surface.
- High-Contrast Text Outlines: Automatic subtle text shadows and stroke borders ensure your watermark remains perfectly readable whether placed over deep shadows, bright skies, or busy textured backgrounds.
- Instant Client-Side ZIP Packaging: Your photos are never sent to external servers or cloud queues. Memory processing is instantaneous, private, and 100% free of file-size or bandwidth limits.
Technical Comparison: CoreFormat vs Standard Online Watermarkers
| Feature | CoreFormat (In-Browser) | Cloud-Based Watermark Tools |
|---|---|---|
| Privacy & Data Security | 100% In-Browser. No photo uploads to remote servers. | Files uploaded to third-party servers and cloud storage. |
| Proportional Scaling | Calculated dynamically per individual photo resolution. | Often applies static pixel sizes that look tiny on 4K photos. |
| Export Capabilities | Individual image downloads or batch ZIP archive. | Watermarking often blocked behind paid subscriptions. |
| Performance & Speed | Instant canvas hardware acceleration on local CPU/GPU. | Subject to server queue delays and network upload speeds. |
| Cost & Limits | Completely free with no image count caps or watermarking ads. | Daily image caps, subscription paywalls, or forced site watermarks. |
Frequently Asked Questions
Can I use my transparent PNG logo as a watermark?
Yes. Select the Logo / Image tab and upload any transparent PNG, SVG, or WebP logo file. You can adjust the scale, opacity, rotation, and anchor position with real-time feedback.
Will watermarking degrade the quality of my original photos?
No. CoreFormat renders your original photo at 100% full pixel resolution and composites the watermark onto a dedicated canvas before encoding at high quality (90% for JPG/WebP, lossless for PNG).
What is Tiled Pattern mode best used for?
Tiled mode repeats the watermark diagonally across the entire surface of the image. This is standard practice for stock photo agencies, client proofs, and digital art portfolios where you want to prevent unauthorized cropping or commercial use.
Are my photos uploaded to your servers?
Never. CoreFormat processes all operations client-side using HTML5 Canvas APIs in your browser RAM. Your original photos, logos, and watermarked outputs never leave your personal computer or mobile phone.