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Image Watermark Tool

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Your image never leaves your device
All processing happens in this browser tab. Nothing is uploaded to any server, and there is no server here to upload it to.

…or drag a photo onto this panel, or paste one from the clipboard. Up to 20 MB and 50 megapixels.

The mark

Text watermark

11/120 characters
A percentage, so the mark is the same size on any image

Bold

Logo watermark

…or drop a logo here. PNG with transparency composites as you would expect, and the file stays on your device like the photo does. Up to 10 MB and 25 megapixels.

Placement

Currently bottom right
Percent of the shorter side, on both axes

Legibility

A white mark disappears on a snow scene and a black one disappears in a night shot. Nothing here samples your photo to guess which you need — a photograph has no single background colour, and a guess that is wrong some of the time is worse than no guess, because you would stop checking the preview.

Applies to the watermark only, never to the photo underneath

Download

JPEG cannot hold transparency
This browser would not let the page read the image back to check for transparency. If your image has transparent areas, JPEG will flatten them; PNG and WebP keep them.

About This Tool

Image Watermark Tool — your mark, added in your own browser

This image watermark tool draws a line of text, a logo file, or both onto a copy of a photo you already own. You load the picture from your device, type your handle or pick a logo, place the mark with a nine-point grid or by dragging it straight across the preview, then download the composited result. The photo is decoded and redrawn by your own browser on a <canvas> element, and no version of it is ever uploaded — there is no server here to upload it to.

What a watermark actually does

A visible watermark is a deterrent and an attribution mark. It makes casual reuse more awkward, and it keeps your name attached to the picture as it travels, so anyone who comes across it can see where it came from. That is a real and useful job, and it is the only job the mark does. A corner mark can be cropped away in seconds; a mark anywhere on the frame can be painted over by someone willing to spend the time. Your copyright in the photograph exists whether or not you stamp it — the mark neither creates that right nor replaces it.

Adding a mark, not removing one
This tool composites a watermark onto an image you own. It does not remove watermarks from anyone else's work, and it is not going to grow that feature.

Why the size is a percentage, not a pixel count

Every size here — the text, the logo, the inset from the edge, the gap between tiles — is a percentage of the image's shorter side. That is not a stylistic choice. 48px of text is a confident signature across a 640 × 480 thumbnail and a barely visible speck on a 6000 × 4000 camera original: one slider value, two completely different pictures, with nothing on screen to tell you which one you were about to download. The preview is also a scaled-down copy, so a pixel figure that looked right on screen would not be the figure applied to the full-resolution file.

Percentages remove that whole class of surprise. Four per cent is four per cent of the frame on any image, the preview and the export are drawn by one function that differs only in its scale factor, and the line of figures under the canvas tells you what your percentage works out to in real pixels for the photo you actually loaded.

Contrast is what makes a mark readable

A white mark disappears into a snow scene; a black one disappears into a night shot. This tool will not sample your image and guess, because a photograph has no single background colour and a guess that is wrong some of the time is worse than no guess — you would stop checking the preview. Instead you pick the light or dark variant yourself, and add a legibility style: an outline strokes a contrasting edge around the mark, a shadow drops a soft blur behind it, and a plate puts a translucent rounded rectangle underneath, which reads most clearly and intrudes most. Opacity is a separate slider, and it applies to the mark alone — never to your photograph.

One mark or many

A single mark in a corner stays out of the picture and is the easiest thing in the world to crop off. A tiled lattice repeats the mark across the whole frame, usually turned about -30°, which is far more work to paint out and considerably more intrusive to look at. Neither setting is correct; they trade the same difference in opposite directions, and the preview is there so you can judge it. Press and hold the before/after control to see the untouched image and decide how much the mark is costing you.

Choosing an export format

PNG and WebP keep an alpha channel; JPEG cannot, so a base image with transparent areas is flattened to a solid colour — black in some browsers, white in others — and the tool warns you when that combination is selected. For an ordinary opaque photo all three are fine, and JPEG or WebP will give you a much smaller file. The quality slider appears only for JPEG and WebP, because PNG is lossless and ignores the quality argument entirely.

Frequently Asked Questions

Is the Image Watermark Tool free?

Yes, Image Watermark Tool is totally free :)

Can I use the Image Watermark Tool offline?

Yes, you can install the webapp as PWA.

Is it safe to use Image Watermark Tool?

Yes, any data related to Image Watermark Tool only stored in your browser (if storage required). You can simply clear browser cache to clear all the stored data. We do not store any data on server.

How does this watermark tool work?

You load a photo from your own device, add a line of text, a logo image, or both, and the tool draws that mark onto a copy of the photo using a canvas in this browser tab. You choose where it sits with a nine-point anchor grid or by dragging it around the preview, how large it is, how far it is turned, how transparent it is, and whether it carries an outline, a shadow or a plate behind it to keep it readable. The preview you see is drawn by exactly the same code that draws the file you download, so nothing changes between the two. When you are happy with it, pick PNG, JPEG or WebP and the composited image is saved to your device.

Is my photo uploaded anywhere?

No. Both the photo and the logo file are decoded by your own browser, drawn onto a canvas on this page, and encoded back into a file your browser saves locally. Nothing is sent anywhere, because there is nowhere to send it: this site is a set of static files with no server, no account and no image endpoint. You can disconnect from the network entirely and every part of this tool still works. It is also why there is no box for pasting an image address. An image fetched from another site taints the canvas, and the browser then refuses to let this page read the pixels back out, so the download would fail at the very last step. Local files only: the file picker, drag-and-drop, or paste from the clipboard.

Can someone remove the watermark from my image?

Yes, and it is worth being plain about that. A visible watermark is a deterrent and an attribution mark, not a lock. A corner mark can be cropped off in seconds, and a mark anywhere on the frame can be painted over or cloned out by anyone willing to spend the time. What the mark actually does is make casual reuse more awkward and keep your name attached to the picture as it travels, so people who see it know where it came from. Your copyright in the photograph exists whether or not you put a mark on it; the mark does not create the right and its absence does not waive it. Tiling the mark across the whole frame and raising the opacity makes removal more work, at the cost of a picture that is harder to look at.

Why is the size set as a percentage instead of in pixels?

Because a pixel size means something different on every image. Forty-eight pixels of text is a confident signature across a 640 × 480 thumbnail and an almost invisible speck on a 6000 × 4000 camera original — the same number, two unrelated results. Worse, the preview on this page is a scaled-down copy of your photo, so a pixel value that looked right on screen would not be the value applied to the full-resolution download. Setting size, offset and tile spacing as percentages of the image's shorter side removes that whole class of surprise: 4% is the same proportion of the frame on both images, and the mark you see in the preview is the mark you get in the file. The figures under the preview show what that percentage works out to in real pixels for the image you loaded.

My watermark is invisible on a light photo. What do I change?

Switch the light or dark variant. A white mark vanishes on a snow scene or a pale studio background, and a black mark vanishes in a night shot, so the variant toggle flips between a white mark with a dark edge and a black mark with a light edge. Then add a legibility style: an outline strokes a contrasting edge around the mark, a shadow drops a soft contrasting blur behind it, and a plate puts a translucent rounded rectangle under it, which is the most readable of the three and the most intrusive. Raising the opacity helps too. The tool deliberately does not sample your photo and pick for you — a photograph has no single background colour, and an automatic guess that is wrong some of the time is worse than no guess, because you would stop checking the preview.

Which export format keeps transparency?

PNG and WebP keep an alpha channel; JPEG cannot and never could. If your base image has transparent areas and you export as JPEG, those areas are flattened to a solid colour — black on some browsers and white on others — so the tool shows a warning when that combination is selected. A watermark drawn onto an ordinary opaque photograph produces no transparency of its own, so for a normal photo all three formats are fine and JPEG or WebP will give you a much smaller file. The quality slider only appears for JPEG and WebP, because PNG is lossless and ignores the quality argument entirely. If your browser cannot write WebP, the tool detects it and names the file after whatever was actually produced rather than mislabelling a PNG.