A preview card image gets copied, cropped and reposted, and a small watermark is the cheapest way to keep your brand attached to it. This tool adds that watermark in your browser: upload your card image, add your logo or a text mark, choose a corner and an opacity, and download the finished image. No account, no upload to a server, and the watermark is baked into the pixels, so it survives reposts that strip metadata.
Logo or text
A logo watermark is best when your mark is already recognisable at small sizes: a simple shape or wordmark reads even at low opacity. Text watermarks suit creators who have no logo file yet; your site name or handle in clean white type works well on most photos. Keep the mark small, roughly a quarter of the image width at most, and keep it in one corner. A giant centre watermark protects nothing better and annoys every legitimate viewer, while a corner mark is enough to prove origin when an image is reused.
Opacity and placement
Opacity around 0.5 is the usual balance: visible enough to read on a busy photo, light enough not to fight the subject. On dark photos, white text at 0.5 reads clearly; on bright photos, the dark outline this tool draws behind the text keeps it legible. Bottom right is the default because eyes finish there, but bottom left avoids the corner where some apps overlay buttons. If your image already has important detail in one corner, pick another; the tool’s five positions cover every corner plus centre.
What a watermark does and does not do
A watermark proves origin and deters casual copying, and it survives screenshots, downloads and re-uploads because it is part of the image. It does not stop a determined person: anyone can crop a corner or paint over a mark with enough effort. For legal protection, a watermark is evidence, not a lock; pair it with keeping your original file and a record of first publication. For everyday sharing, though, a corner mark is exactly the right weight.
Privacy
Both images are processed locally on your device. Nothing is uploaded, stored or sent to any server, and the downloaded file contains only the pixels you see.
A consistent batch workflow
Watermarks work best as a habit, not a one-off. Pick one corner, one opacity and one mark, and use the same combination on every image in a series, so readers learn to recognise your cards at a glance and reposts are easy to trace back to you. Always keep an unwatermarked master copy of every image: once a watermark is baked into the only copy, you cannot remove it cleanly, and a future redesign of your logo would mean rebuilding every card from scratch. Name your files so the watermarked version is obvious, for example adding -wm to the file name, and store masters and watermarked copies in separate folders. If you publish the same image in several sizes, watermark the largest version first and then resize, because a mark added to a small image and then enlarged turns soft, while a mark added large and shrunk stays crisp. Finally, review watermarked images on a phone before publishing: a mark that looks subtle on a monitor can disappear entirely on a small bright screen, and one that looks bold on a monitor can dominate a phone card.
When not to watermark
Not every image benefits from a mark. Images meant for press use, for partners who will repost with credit, or for print often look cleaner without one, and a watermark on those can read as distrust towards people you actually want to share your work. Client deliverables are another exception: a watermark on a final delivered file can look unfinished, so deliver clean files and keep watermarked versions for previews and social posts only. Finally, skip the watermark when the image itself is the product being sold, such as stock photography or digital art prints, because buyers judge quality from the preview and a heavy mark hides exactly what they are deciding about. In those cases a light preview mark on a low-resolution sample, with the clean full-resolution file delivered after purchase, is the standard balance.
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