What is Add Overlay to Image Online?
Image Overlay composites either a second image—usually a PNG sticker, badge, or logo—or a solid color block onto a base photo with free placement. The ToolSphere draws layers on a canvas, applies size and opacity, and exports JPEG, PNG, or WebP.
Unlike corner-snapped watermarking, overlay placement is drag-based so you can sit a mark on any quiet region, add a color bar, tint the full frame, or build a simple composite without leaving the browser.
Transparent PNGs keep soft edges. Image overlays scale by base width while preserving aspect ratio. Color overlays use independent width and height fractions of the base. Opacity uses canvas globalAlpha on the overlay layer only.
Why Use This Tool?
Designers and marketers often need a quick sticker, color bar, or tint before a full editor. Local overlay keeps drafts off upload converters.
Use Watermark Image when you want fixed proof marks; use Image Overlay when placement must be freeform or you need a color layer.
- Image or solid color overlay
- Drag-to-position layer
- Size and opacity controls
- JPEG, PNG, WebP export
- Runs in your browser without uploading to The ToolSphere servers
How Does This Tool Work?
Image mode loads a second file and draws it with applyImageOverlay. Color mode fills a rectangle with applyColorOverlay. Dragging updates pixel coordinates; encode uses canvas.toBlob.
Because composition is flattened into pixels, resize or crop the base first when the final frame size is already known.
Understanding Your Results
If an image overlay looks soft, export PNG or raise JPEG/WebP quality. If edges look boxed, the overlay file likely lacks transparency—prefer PNG.
For a full-frame tint, set color width and height to 100% and lower opacity. Dragging near edges clamps so the layer stays inside the base frame.
Why Tracking This Matters
Simple composites and color treatments are a common publish step. Doing them locally avoids sending unpublished creative to a third-party upload API for this tool.
Benefits of Using Add Overlay to Image Online
- Image or color overlay modes
- Free placement instead of fixed corners
- Live preview while dragging
- Opacity control for subtle layers
- Format choice on download
- Transparent PNG overlay support
- Local Canvas processing—no The ToolSphere server upload for this tool
How Is the Result Calculated?
Image overlay width = round(baseWidth × scale); height preserves overlay aspect. Color overlay width = round(baseWidth × widthScale); height = round(baseHeight × heightScale). Opacity is canvas globalAlpha in [0, 1].
- scale / widthScale
- Layer width as a fraction of base width.
- heightScale
- Color layer height as a fraction of base height.
- opacity
- 0–1 alpha for the overlay layer.
- x, y
- Top-left of the overlay in base image pixels.
- color
- CSS color used for color-mode fillRect.
Tips for Better Results
- Prefer PNG overlays with alpha for clean edges.
- Use color mode at 100% size with low opacity for a photo tint.
- Lower opacity when the subject must stay readable.
- Crop or resize the base before overlaying when publishing to a fixed size.
- Use Watermark Image for repeated corner proof marks.
- Export PNG when you need lossless flattening.
Standards and References
Conclusion
Image Overlay places a drag-positioned image or color layer with size and opacity, then exports from your browser. Use it for stickers, bars, and tints; keep Watermark Image for quick corner proof marks.