The Image Watermark tool adds text watermarks to images entirely in your browser — no file is uploaded. It supports two placement modes (single-point and tiled), and lets you adjust opacity, font size, rotation angle, and output format.
Single-Point vs. Tiled Mode
The two modes have noticeably different protection levels:
Single-point positioning
- Places the watermark at a fixed location (nine anchor points, or custom percentage coordinates)
- Least visual interference — doesn't obscure the subject
- Easy to remove by cropping or painting over a corner
- Good for attribution, corner URLs, or usage notes on ID photos
Tiled (repeat)
- Repeats the watermark across the entire image at a fixed spacing
- Spacing range: 8–400 px (default 24 px — larger spacing = less dense)
- Difficult to remove without visibly damaging the image content
- Good for sample images, design proofs, and high-value photography
Opacity in Practice
Opacity ranges from 0 to 1, defaulting to 0.5. What each range looks like:
- 0.15–0.3: Barely visible, display-only use, won't obscure the subject
- 0.4–0.6: Clearly readable without being distracting — the default range for most cases
- 0.7–1.0: Strong protection, very visible — suitable for sample images or document anti-theft
For tiled watermarks, visual density is the combined effect of opacity and spacing. The default 24 px spacing at opacity 0.5 is already quite prominent on most images. For a subtle approach, try spacing 60–100 px with opacity 0.2–0.3.
Matching Font Size to Image Dimensions
Font size ranges from 12 to 240 px, defaulting to 32 px. The right size depends on the image's pixel dimensions, not just how it looks on screen:
- Image width under 800 px: 20–40 px
- Image width 800–2000 px: 40–80 px
- Image width over 2000 px (full-resolution photos): 80–160 px to stay readable when printed or zoomed
Rotation Angle and Anti-Removal
Rotation ranges from -180° to 180°, defaulting to 23°. Angled watermarks are harder to remove with automated tools than horizontal ones. In practice, a tiled watermark at 15–45° offers the best resistance; a 0° horizontal tile can be bypassed by some scripted cropping patterns.
JPEG Export Quality
When exporting as JPEG, quality ranges from 0.1 to 1, defaulting to 0.9. Below 0.7, thin-stroke text watermarks (like small-font URLs) lose legibility in compression artifacts. If the watermark is critical information, keep quality at 0.85 or above, or use PNG.
PNG is the right choice for images with transparent backgrounds. JPEG is better for photos where you need to control file size. When exporting as JPEG, the tool automatically fills transparent areas with white.