Should you watermark a photo before posting it?

What a watermark actually protects

A visible handle can help a viewer identify the source you claim for a photo. It does not verify authorship or guarantee removal of a repost. Check the platform's current picture policy before adding a mark to a public listing.

It is a label, not a claim you can enforce. A watermark is not a copyright registration and not a C2PA signature, so it carries no proof that you pressed the shutter. The AI-generated preset works the same way: readable, not verifiable.

So the useful test is not whether a mark stops theft, because it does not. A mark earns its place when it survives the crop and stays legible at thumbnail size. One that gets trimmed off, or sits so faint that nobody reads it, is decoration with a cost.

Where to put it so the crop does not eat it

The usual spot is the bottom right corner, which is also the first thing a 1:1 listing card, a 4:5 crop, or a lazy screenshot removes. Anyone who wants your photo without your name trims a few hundred pixels off one edge and walks away with it.

What survives is a mark over the subject itself, or repeat turned on so the pattern covers the frame. Both are harder to look at and much harder to cut out, which is the whole trade.

1. Crop the photo to the shape the platform shows before you place the mark.
2. Put the text over the part of the subject you cannot afford to lose.
3. Turn repeat on if a single mark still sits in a croppable corner.

How visible is too visible

Choose opacity by inspecting the mark over the actual photo and at the size recipients will see. About 45% can be a trial setting, not a proven optimum. Adjust it if the background hides the text or the mark obscures the subject.

A mark can obscure useful product details. Compare the marked photo at listing size, and check whether the platform allows text overlays. For a private proof, choose a placement that remains legible without covering the information the recipient needs.

Check the platform's watermark policy

eBay's picture policy prohibits watermarks of any type, including ownership attributions. Keep a separate unmarked copy for an eBay listing.

Other marketplaces have their own policies. Check those instructions before using Watermark image for an upload. A private proof and a public listing can need different versions of the same photo.

What it does not stop

Someone with an editor can crop past a corner mark, paint over a light one, or run a generative fill across it. A repeated pattern at real opacity makes that expensive rather than impossible.

The mark also does nothing about what sits under the pixels. GPS, camera model, and timestamp stay in the file until you strip them with Remove EXIF. If the photo is of your own house, do that first: strip GPS.

When not to watermark

Skip it on a Marketplace cover. The feed reads stamps and prices as junk and the cover is already the click, so a mark there costs more than it protects: listing photo size.

Skip it on anything a chat will recompress, because a faint mark comes out as mush on the other side: WhatsApp original. Skip it on document and ID uploads, where a portal wants the page unaltered, and on files going to a print lab, which will print the mark exactly as you left it.

Stamp the batch once you have decided

Watermark image takes up to 80 characters of text, or a logo file under 24 KB, and puts it in a corner, in the centre, or repeated across the photo. HEIC, JPEG, PNG, WebP, and AVIF all go in, up to 10 files, 20 MB each. HEIC comes out as JPEG. JPG, PNG, WebP, and AVIF keep their format.

A logo replaces the text stamp rather than joining it, and a PNG with a transparent background sits far better than a white box. iPhone HEIC is decoded through the same libheif path as HEIC to JPG, so the mark is baked into the pixels.

1. Drop the photos on Watermark image.
2. Type the handle or pick a small logo, then set the position and opacity.
3. Turn repeat on if a crop would remove a corner mark, then download the files or the ZIP.