How do I keep watermarks consistent across photos of different sizes?

Size on this page is a percentage of each image's shorter side. With the same 6% setting, a 4000×3000 photo gets 180 px text and a 1200×800 photo gets 48 px text, so the watermark looks proportionally the same on both. Margins and tiling gaps also use percentages of the shorter side, which keeps a whole batch of mixed sizes visually consistent without adjusting each image by hand.

How do I add a diagonal tiled watermark against misuse?

Choose the tiled layout, set the angle to about −30° and the opacity to 30%–40%, then adjust the spacing until the pattern looks right. The watermark covers the whole image with staggered rows, which is much harder to crop away than a single corner mark. No watermark can fully prevent removal, though, so avoid publishing important originals in full resolution.

Which file format works best for a logo watermark?

A PNG or WebP with a transparent background works best; a JPEG logo carries a white rectangle with it. Logo width equals the shorter side × the size setting × 2.5, so at 6% the logo spans about 15% of the shorter side. Logo files may be up to 10 MB, and an opacity of roughly 40%–60% usually keeps the mark visible without overpowering the photo underneath.

Image Watermark — Batch Add Text and Logo Watermarks

Set the watermark text or upload a logo, then drop images. Position, size and opacity changes update the preview automatically; download or bundle as ZIP.

Example

Input

sample.png (generated, 1200×800) · text SAMPLE · tiled · −30° · opacity 35% · size 6%

Example result

sample-watermark.png · 1200×800, 48 px text (800 × 6%) tiled diagonally across the image

On a 4000×3000 photo the same 6% setting produces 180 px text, keeping the visual proportion the same.

Technical details & limits

Text size equals the image's shorter side × the size percentage; logo width equals the shorter side × the size percentage × 2.5, with height following the logo's ratio. A single watermark is positioned by its rotated bounding box, with the margin also a percentage of the shorter side. Tiling fills a grid covering the whole image in the rotated coordinate system, offsetting alternate rows by half a unit. The text outline is 8% of the font size, in a dark or light shade chosen to contrast with the text color. The watermark is drawn into the pixels and the result is re-encoded without EXIF.

About this tool

Batch-add watermarks locally in your browser. Use text with font, color and outline options, or upload a PNG, WebP or other logo. Place it at any of nine positions or tile it diagonally across the whole image. Size, margin and spacing are percentages of each image's shorter side, so different photo sizes look consistent. Opacity and rotation are adjustable, output can be the original format, JPEG, PNG or WebP, and a comparison preview and ZIP bundle are included.

How to use

Drop, choose or paste images, up to 30 at a time.
Choose a text or image watermark, single or tiled, and adjust position, size, opacity and angle.
Check the comparison preview, then download single files or a ZIP.

Input & output

Input: JPEG, PNG, WebP, AVIF, BMP or GIF (first frame) photos, up to 30 at a time and 50 MB each; logos up to 10 MB, ideally a transparent PNG.
Output: Watermarked JPEG, PNG or WebP files, downloadable singly or as a ZIP.
Limits: Text up to 200 characters in system fonts; no multi-line text or custom font files; metadata and animation are not kept.

Notes

A watermark raises the cost of misuse but cannot fully prevent cropping or removal. Tiled, more opaque marks over the main subject are harder to remove.

FAQ

How do I keep watermarks consistent across photos of different sizes?: Size on this page is a percentage of each image's shorter side. With the same 6% setting, a 4000×3000 photo gets 180 px text and a 1200×800 photo gets 48 px text, so the watermark looks proportionally the same on both. Margins and tiling gaps also use percentages of the shorter side, which keeps a whole batch of mixed sizes visually consistent without adjusting each image by hand.
How do I add a diagonal tiled watermark against misuse?: Choose the tiled layout, set the angle to about −30° and the opacity to 30%–40%, then adjust the spacing until the pattern looks right. The watermark covers the whole image with staggered rows, which is much harder to crop away than a single corner mark. No watermark can fully prevent removal, though, so avoid publishing important originals in full resolution.
Which file format works best for a logo watermark?: A PNG or WebP with a transparent background works best; a JPEG logo carries a white rectangle with it. Logo width equals the shorter side × the size setting × 2.5, so at 6% the logo spans about 15% of the shorter side. Logo files may be up to 10 MB, and an opacity of roughly 40%–60% usually keeps the mark visible without overpowering the photo underneath.

Related tools

Image watermark — Tool illustration · dayeku.com

Comparison