Image Watermark

The Image Watermark tool adds customizable text watermarks to images for copyright protection, branding, or attribution. Photographers watermark portfolio images to discourage unauthorized use. Brands add watermarks to marketing images. Social media content creators watermark to credit their work when images get reshared. Users preparing documents may watermark \\\"DRAFT\\\" or \\\"CONFIDENTIAL\\\" on screenshots. All common use cases covered with one tool.

Configure watermark text, font family, size, color, opacity (for transparent effect), position (corners, center, tiled across whole image, diagonal), and rotation angle. Preview updates in real time. Supports JPG, PNG, WebP, GIF, BMP. Preserves transparency for PNG and WebP. All processing runs in your browser — original images, watermark text, and output never leave your machine. For batch watermarking (many images), this tool processes one at a time in the current version.

Text watermarking uses Canvas 2D text rendering:

1. Load image into canvas
2. Set font family, size, style
3. Set fill color with alpha (transparency)
4. Apply transform (translate to position, optionally rotate)
5. Draw text at desired position
6. Export canvas as image

Fonts: the browser has system fonts available. For guaranteed fonts, use web-safe fonts (Arial, Helvetica, Times New Roman, Courier) or load web fonts (Google Fonts). The tool uses a curated list of common web-safe fonts by default.

Opacity: setting text fill with alpha channel (e.g., rgba(255, 255, 255, 0.5)) makes text semi-transparent. Common watermark opacity: 20-60% for subtle; 70-100% for prominent.

Position presets:
- Top-left, top-right, bottom-left, bottom-right: common for copyright
- Center: prominent branding
- Tiled/repeated: covers whole image (hardest to remove)
- Diagonal across center: common for \\\"DRAFT\\\" or \\\"SAMPLE\\\"
- Custom X/Y coordinates

Rotation: apply ctx.rotate() before drawing text for diagonal or angled watermarks. Typical diagonal angle is -30° or 45° from horizontal.

Text shadow: optional shadow behind text for visibility against complex backgrounds. Makes watermark readable on any image.

Font metrics: Canvas measures text width with ctx.measureText(text).width but doesn\u2019t give height directly. Height is approximated from font size (usually font size × 1.2 for line height).

Outline stroke: for maximum visibility on complex backgrounds, draw text with both fill and stroke (stroke a contrasting color, fill the primary color).

Image-as-watermark (logo): more advanced than this text tool. For image watermarks (logo overlay), upload a second image with transparency and composite at chosen position. This text-only tool focuses on text watermarks.

Batch processing: the current tool handles one image at a time. For batch watermarking, process each image and download individually, or use a dedicated batch tool.

Anti-removal: determined actors can remove watermarks with image editing tools. For real copyright protection, register copyright officially; watermarks are deterrent, not perfect protection.

Compared to Photoshop watermarking, this tool is free and instant. Photoshop offers action-based batch processing and more text effects; this tool is faster for single-image watermarking.

Compared to phone watermark apps, this tool preserves image quality better (no mobile-specific compression). Phone apps are convenient for quick watermarking; this tool is better for quality-critical work.

Compared to built-in camera watermark features, this tool offers much more customization. Camera watermarks are minimal; this tool gives full design control.