How the text watermark is placed
The photo is drawn onto a canvas at its full original pixel size, and your text is painted over it with the canvas fill colour and a global alpha equal to the opacity slider (5 to 100 percent, default 50). The font is bold system-ui, and its size is a percentage of the image's shorter side: fontSize = round(min(width, height) x size / 100), never below 10 px. Because it scales with the image, the same setting looks proportionate on a thumbnail and on a 24-megapixel photo.
Worked example
A 4000 by 3000 photo with the default 6 percent size gets a font of round(3000 x 6 / 100) = 180 px. Corner marks sit 0.6 x 180 = 108 px in from the edges, so in the bottom-right the right-aligned text ends at x = 3892 and its centre line is at y = 2802. On a 1200 by 800 image the same setting gives 48 px text, ending at x = 1171.
| Position | Behaviour |
|---|---|
| Four corners | Aligned to the corner with a padding of 0.6 times the font size |
| Center | Centred horizontally and vertically |
| Tiled | Repeats across the whole image, rotated -30 degrees, horizontal step = text width + 3 font sizes, vertical step = 4 font sizes |
The "Diagonal" option, for the non-tiled positions, rotates the text -30 degrees around the middle of the text and positions that rotated block so it stays inside the image, with the same padding in from the chosen corner. Text wider than the image is centred instead.
Making it readable and hard to remove
The mark is a single flat colour with no outline or shadow. White at 50 percent opacity will almost vanish on a snowy or overexposed area, so check the preview over the brightest part of the picture and switch the colour to black or a brand shade if needed. A faint tiled pattern across the subject is far harder to crop out than a corner mark, since cropping removes a corner but cannot remove text that crosses the middle. No watermark is permanent, and a tiled one can be partly restored by editing tools.
Common mistakes
- Diagonal corner marks are kept inside the image, but very long text at a large size can still be wider than the picture, because nothing wraps. Shorten the text or lower the size.
- Very long text at a large size will extend beyond the image width, because nothing wraps.
- Only text is supported: there is no logo upload, so use a symbol such as the copyright sign in the text if you want one.
- JPG and WebP exports use 92 percent quality; PNG is lossless but bigger. The download keeps your file name with
-watermarkedadded. Shrink big files afterwards with the image compressor. - For documents instead of photos, the PDF watermark tool applies the same idea per page.