How this works in your browser
Your photo is drawn onto a canvas at full resolution, then the watermark is composited on top of it with the global alpha set to your chosen opacity. Text is rendered through the canvas text engine at a size scaled to the image, so the mark stays proportionate on a small crop and a large export alike; a logo is drawn as a second image with the same alpha applied. Tiling repeats that draw across a grid covering the whole frame. The result is flattened into a single image on export, which means the watermark becomes part of the pixels rather than a separate removable layer. Everything happens in your browser, so unreleased client work and personal photos never leave your device.
Watermark Adder vs. traditional online converters
| Feature | Watermark Adder (in-browser) | Traditional online converters |
|---|---|---|
| File upload required | No - never leaves your device | Yes - file is sent to a server |
| Processing queue | None - starts instantly | Often, especially at peak times |
| Watermark on output | Never | Common on free plans |
| Usage limits | None - free, unlimited use | Often capped per day or file size |
| Works offline once loaded | Yes, for most tools | No - requires a live connection |
| Account required | No | Often, for anything beyond a trial |
Who uses Watermark Adder
Client proofs before payment
Mark preview images clearly so they cannot be used until the invoice is settled.
Protecting portfolio work
Brand photographs before posting them publicly so reuse is traceable back to you.
Consistent social branding
Apply the same handle or logo across a set of posts so reshared images still credit you.
Marking documents and screenshots
Stamp internal captures with a confidential or draft label before circulating them.
How to use Watermark Adder
- 1
Open the Watermark Adder
Go to tools.slaytic.com and open the Watermark Adder. No sign-up or account required.
- 2
Drop the image to watermark
Add your photo. Neither it nor your logo is uploaded anywhere.
- 3
Choose text or a logo
Type the text you want, or supply your own logo image to use instead.
- 4
Set position and opacity
Pick a corner, the centre or a tiled repeat, and adjust how visible the mark should be.
- 5
Download the result
Save the watermarked image, ready to post or send to a client.
Frequently asked questions
Can I use my own logo instead of text?
Yes, upload a logo image to use as the watermark instead of typed text.
Can I control how visible the watermark is?
Yes, an opacity slider controls how subtle or prominent the watermark appears.
Can I position the watermark anywhere?
Yes, choose from common positions like corners and centre, or a tiled repeat across the whole image.
Can someone remove the watermark?
A determined person with editing skills can reduce or clone out a corner watermark, and it is worth knowing that rather than assuming otherwise. A tiled watermark across the whole frame is much harder to erase cleanly, because there is no untouched region to sample from. Treat a watermark as a strong deterrent and a clear ownership signal, not as an unbreakable lock.
What opacity actually works?
Somewhere around 30 to 50 percent suits most images. Too faint and it is trivial to remove or simply ignore; too strong and it fights the photograph. For client proofs, err on the prominent side, since the point is to make the unpaid version unusable.
Where should I place it?
A corner keeps the image presentable and suits portfolio or social posting. Centre or tiled is the choice for proofs and anything you genuinely expect people to try to lift. Match the placement to how much you care about the specific image.
Does watermarking give me copyright?
No. You already hold copyright in your own work from the moment you create it. A watermark does not add legal rights, it makes ownership visible and makes casual reuse inconvenient, which in practice is what stops most of it.
Is my image uploaded anywhere?
No. The watermark is composited inside your browser tab.