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Add Watermark
Protect images with custom text or image watermarks. Control position, opacity, size and color.
Choose an image to watermark
Add text watermarks to protect your images
Add Watermark — 無料＆プライベート
Add text watermarks to your images instantly in the browser. Choose position, font size, opacity, and colour to protect your photos with a professional-looking mark.
All watermarking happens locally — no upload, no account required. Unlike online tools that process on their servers, your originals stay completely private.
使い方 Add Watermark
- Drop or select your image.
- Type your watermark text (e.g. "© Your Name 2025").
- Adjust font size and opacity to your preference.
- Select a position (corner or centre).
- Click Add Watermark and download.
なぜ私たちを選ぶ Add Watermark?
- 100% Private — Canvas-based, no server ever
- Five placement positions
- Adjustable opacity for subtle or strong marks
- Customisable font size
- No account, no watermarks on output (from us), no limits
- Instant results, works offline
よくある質問
How do I add a watermark to an image online?
Drop your image in, type your watermark text, choose position and opacity, and click Add Watermark. Download the protected image instantly.
Can I control where the watermark appears?
Yes. You can place the watermark in any of five positions: top-left, top-right, centre, bottom-left, or bottom-right.
How do I make the watermark transparent or semi-transparent?
Use the Opacity slider. 100% is fully opaque; lower values (e.g. 40–60%) create a subtle, semi-transparent watermark.
What font size should I use for a watermark?
For large images (2000+ px wide) use 60–100 px. For smaller images use 24–48 px. The live preview shows how it looks before you download.
Are my images uploaded when I add a watermark?
No. Watermark rendering runs entirely in your browser using the Canvas API — your images never leave your device.