Image Watermark
Drop or choose a photo and add a text or logo watermark — set the size, color, opacity, position, and rotation, or tile it diagonally across the whole image. The watermark is composited on a canvas inside your browser and saved straight to your device.
Your image never leaves your browser and is never uploaded to any server.
What is the Image Watermark?
This is a free, browser-based image watermark tool. Drop in or choose a photo and add a text
watermark — your name, your studio, a copyright line, or a "DRAFT" stamp — with full control over
its font size, color, opacity, position, and rotation. You can place a single discreet mark in any
of nine grid spots, or tile the text diagonally across the whole picture so it cannot easily be
cropped out. You can also overlay your own transparent PNG logo. Everything happens on your device:
the image is decoded, the watermark is drawn on a hidden <canvas>, and the result
is saved locally. The picture is never uploaded.
How to use it
- Add your image — click to choose a file, drag and drop it onto the drop zone, or paste with Ctrl+V (Cmd+V on Mac).
- Type your watermark text, then set the font size, color, and opacity until it reads clearly without hiding the photo.
- Choose a position from the nine-point grid, or turn on Tile to repeat the watermark across the entire image.
- Optionally set a rotation angle, and load a transparent PNG logo to overlay instead of, or alongside, the text.
- Watch the live preview update, then click Download. The watermarked file saves straight to your device.
The method behind it
The watermark is composited with the HTML Canvas API. Your photo is first decoded into an
off-screen image so the browser knows its true pixel dimensions, then a canvas is created at exactly
that size and the original picture is painted onto it. Next the tool sets the canvas global alpha
from your opacity value, picks the font size as a percentage of the image's shorter side so the mark
stays proportional on both landscape and portrait pictures, and draws the text. A single watermark
is anchored to one of nine points with the correct text alignment for that corner or edge, plus a
small inset margin that scales with the image. For tiling, the canvas is rotated by your chosen
angle and the text is stamped on a grid of points spaced by a density-driven step, over-scanning
past the edges so the rotated pattern still fills every corner. Finally the canvas is exported with
toBlob in your chosen format and downloaded.
Examples
- Sign a portfolio photo: type your studio name, set opacity to about 40, choose the bottom-right position, and export as PNG for a clean, discreet corner signature.
- Protect a public proof: turn on Tile, set a 45-degree rotation, and type "PROOF — DO NOT COPY". The text repeats diagonally across the whole image, far harder to crop out than a single mark.
- Brand with a logo: load a transparent PNG of your logo, place it top-left at low opacity, and download. Your mark sits cleanly on top of the photo with no solid box behind it.
Common use cases
- Photographers and illustrators protecting their work before posting it to social media or portfolios.
- Adding a copyright line or website URL so reshared images still point back to you.
- Stamping "DRAFT", "CONFIDENTIAL", or "SAMPLE" on documents, mockups, and client previews.
- Small businesses branding product shots, screenshots, and marketing images with a logo.
- Discouraging image theft on listings, blogs, and e-commerce pages with a tiled watermark.
Why use this one
Most online watermark tools upload your photo to a server, queue it, sometimes add their own brand to the result, and cap how many images you can do for free. This one does none of that. The picture is read and watermarked entirely in your browser, so it never leaves your device — which makes it safe for private photos, ID scans, internal proofs, and client work. There is no sign-up, no forced third-party watermark, no upload wait, and no limit. Because the work happens locally, the preview is instant and the watermarked image is yours alone.
It is part of a small image toolkit. To change a picture's dimensions, use the Image Resizer; to make a file lighter without changing its size, use the Image Compressor; and to keep only part of a picture, try the Image Cropper.
Frequently asked questions
Is my image uploaded to a server when I add a watermark?
No. The picture is decoded and the watermark is drawn entirely inside your browser on a hidden canvas, then saved straight to your device. Nothing is sent over the network, stored, or logged, so private photos, proofs, ID scans, and client work stay on your machine. Close the tab and nothing remains.
How do I position the watermark exactly where I want it?
Pick one of the nine grid spots — the corners, the edge centers, or the middle — and the watermark is anchored there with a small inset from the edge. Corners are the usual choice for a discreet signature, while the center is best for proofs you do not want reused.
Can I repeat the watermark across the whole image?
Yes. Turn on Tile to stamp the watermark over and over at an angle so it covers the entire picture. A tiled diagonal pattern is far harder to crop or clone out than a single mark, which makes it a strong choice for protecting work you publish publicly. A density slider sets how tightly the repeats sit.
Can I use my own logo instead of text?
Yes. Load a transparent PNG logo and it is drawn on top of your photo at an adjustable size and opacity, in the same nine grid positions as the text. Use a PNG with a transparent background so only your mark shows, not a solid rectangle behind it.
Does adding a watermark reduce the image quality?
The photo itself is redrawn at its original pixel size, so it is not softened. Saving as PNG is lossless and keeps every pixel; saving as JPEG re-encodes the picture and can introduce slight compression, which is usually invisible at high quality. Choose PNG when you want a perfect copy with the mark applied.