Watermark an image

1. Choose a JPG, PNG or WebP. The file is read locally; nothing is uploaded.
2. Pick text or logo, then set the size, colour, opacity and rotation.
3. Choose a corner for a signature or turn on “Repeat across the image” for a preview that is harder to crop.
4. Download the full-size PNG, JPEG or WebP and check it on the device your buyer uses.

There are two different jobs. A signature — a small name or logo in a corner — tells people where the image came from. It is easy to crop, which is fine for a portfolio or a social post. A preview watermark is there to make the image less useful to steal; it needs to cross the subject, not sit in a corner.

A tiled watermark is harder to remove than a single stamp, but it also obscures more of the image. For a paid product, the usual pattern is a lower-resolution preview with a tiled mark and a clean, full-resolution file delivered to the buyer. The preview sells the work; the clean file is what they pay for.

Text is faster and easier to read: a name, a handle, “DRAFT”, “PROOF” or a client’s name. A logo is more recognisable but needs a transparent PNG and a size that survives the reduction to a social feed. If the logo is detailed, use the text version at small sizes and the logo at large ones.

Contrast matters more than colour. White text with a dark outline works on most photos; black text works on light ones. The outline control is there for busy images where a flat colour disappears.

The same tool covers a few different jobs: a preview for a photo pack, a proof for a client gallery, a mark on a social post, or a buyer-specific mark on a delivered file. For a product you sell repeatedly, the preview and the paid file should not be the same file. Watermark the preview, keep the clean master, and deliver the clean version through a link that can expire or be capped.

See selling photo packs, stock photos or digital art for the product side, and Unlockable’s pricing for the link.

A watermark is a deterrent and an attribution mark. It makes an image less convenient to reuse and easier to trace. It is not DRM: a determined person can crop it, clone it out or reconstruct the image. It does not stop screenshots, and it does not control who sees the file.

That is why the strongest protection is a combination: a visible mark on the preview, a clean file delivered to the buyer, and a link that is tied to the purchase rather than a public URL. The watermark handles the visible part; the link handles the access part.

The tool uses the Canvas API to read the image and draw the watermark. There is no upload request, no server-side copy and no account. If you want to check it, load the page, turn off your network, and process an image. It still works, because the file is local.

The same is true of the PDF tool. The only network requests on this page are the page’s own assets; the image data is not sent anywhere.

Batch processing is not in this release. It is on the list because it is the most requested feature for a photo pack: the same mark on 20 images should not take 20 rounds of settings. Until then, the settings stay in place when you choose a new image, so the repeated part is the file picker rather than the whole form.

Use the PDF watermark tool for a document, or how to sell digital products on Instagram for the distribution side. For the difference between a watermark and access control, see how to stop customers sharing your download link.