Add text or image watermarks to protect your photos. Features position control, opacity adjustment, tiled patterns, and batch processing for copyright protection.
A watermark is a compositing operation: your mark is drawn on top of the original image with some blend mode and opacity, then the result is flattened back into a single-layer output. For text watermarks, opacity between 25-40% is usually the sweet spot, visible enough to credit or identify ownership, faint enough not to dominate the image. Pure 100% opacity text is rarely what you want unless you are stamping "DRAFT" or "CONFIDENTIAL" across something where legibility matters more than subtlety. For logo watermarks, PNG with transparency is essential; using a JPEG logo forces you to composite its rectangular background into your image, which is almost never what you want. Placement matters as much as opacity. Corner placement (often bottom-right) is the social media standard because it stays out of the subject; viewers can see the mark without it competing with the main image. Tiled or diagonal placement across the full frame is stronger protection for portfolio previews because it is much harder to clone-stamp out cleanly, but it also makes the image less appealing to view. The right tradeoff depends on whether you are protecting high-value unreleased work or just branding shareable content.
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You are sharing proofs and need a semi-transparent logo tiled across each image to deter reuse.
Input
proof.jpg + logo.png · 30% opacity, tiled, 45°
Output
proof_wm.jpg with a repeating diagonal watermark
A low-opacity tiled mark is hard to crop or clone out while staying unobtrusive on the actual content. Batch mode applies identical placement to a whole gallery so proofs are protected consistently.
A watermark is a compositing operation: your mark is drawn on top of the original image with some blend mode and opacity, then the result is flattened back into a single-layer output. For text watermarks, opacity between 25-40% is usually the sweet spot, visible enough to credit or identify ownership, faint enough not to dominate the image. Pure 100% opacity text is rarely what you want unless you are stamping "DRAFT" or "CONFIDENTIAL" across something where legibility matters more than subtlety. For logo watermarks, PNG with transparency is essential; using a JPEG logo forces you to composite its rectangular background into your image, which is almost never what you want. Placement matters as much as opacity. Corner placement (often bottom-right) is the social media standard because it stays out of the subject; viewers can see the mark without it competing with the main image. Tiled or diagonal placement across the full frame is stronger protection for portfolio previews because it is much harder to clone-stamp out cleanly, but it also makes the image less appealing to view. The right tradeoff depends on whether you are protecting high-value unreleased work or just branding shareable content.
Mark preview images to protect your work while sharing it online.
Stamp documents with "Draft""Confidential"or other labels.
Add your logo to images shared on social media or third-party sites.
The watermark pipeline runs as a canvas composite operation. Your text is rasterized into a transparent layer using the selected font, size, and color; logos are loaded as separate image layers. Each layer is drawn onto the source image at the specified position using globalAlpha for opacity and optionally a rotation transform for angled watermarks. The final canvas is then re-encoded in your chosen output format. For photographic sources this typically means JPEG or WebP output; for work with transparency or sharp text edges, PNG preserves watermark legibility better because JPEG's 8x8 DCT blocks can introduce ringing around high-contrast text.
A few technical considerations. Font rendering differs subtly between browsers and operating systems, so a watermark created on macOS may look slightly different rendered on Windows even with the same specified font. For consistent output across machines, stick to web-safe fonts or provide the font as an uploaded asset. If you add a text watermark at the same size to images of different resolutions, it will appear dramatically larger on low-resolution images and smaller on high-resolution ones; most tools specify watermark size as a percentage of image width to compensate, which this one does when you adjust the size slider relative to the image rather than in absolute pixels.
On removability: visible watermarks deter casual theft but do not provide cryptographic protection. An attacker with Photoshop and 20 minutes can usually reconstruct watermarked regions convincingly, especially corner-placed semi-transparent marks on uniform backgrounds. Tiled full-frame watermarks are harder to remove but make the image less useful even for legitimate preview. For work where provenance matters beyond social deterrent, consider pairing a visible watermark with an invisible metadata tag (IPTC or XMP) and keeping the original file with registration details.
Yes. The opacity slider lets you control transparency from fully visible to barely perceptible.
Yes. Upload any PNG image (ideally with a transparent background) to use as an image watermark.
A well-placed, semi-transparent watermark is difficult to remove cleanly without degrading the underlying image, which is the point. For maximum protection, use tiled or full-coverage placement.
Images are decoded, edited, and exported entirely inside this browser tab. No originals, exports, or metadata are uploaded.