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Add a Watermark to an Image — Free, No Upload

Add a text watermark to any image free in your browser — no signup, nothing uploaded. Choose the text, color, size, position, and opacity, then download instantly.

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JPG, PNG, WebP · Files never leave your browser.

Upload an image to get started.

How to watermark an image

  1. Drop your photo or image onto the tool — a live preview appears immediately.
  2. Type your watermark text.
  3. Pick a color and a position: a diagonal center mark, or a corner/edge placement.
  4. Adjust size and opacity until it looks right in the preview.
  5. Click Download.

Everything renders live on an HTML5 canvas as you adjust settings, so you see the exact result before downloading.

When to watermark a photo

  • Portfolio previews — photographers and designers watermark proofs so a client can review the work without the full-resolution, mark-free version circulating before payment.
  • Attribution — a website or social handle stamped on images meant to be shared, so credit travels with the image even if it's reposted elsewhere.
  • Draft or sample marking — indicating an image isn't the final deliverable.
  • Discouraging casual reuse — a visible mark doesn't prevent copying, but it does discourage casual reuse of an image found via search or social media.

A watermark is a deterrent and an attribution device, not a security measure — someone determined enough can crop or edit around it. It's most effective as a visible signal of ownership on images meant to be seen widely, not as a barrier against a determined bad actor.

Choosing position and style

A diagonal center watermark (the default here) is the hardest to crop out without losing important parts of the image, since it spans the middle of the frame — the standard choice for stock photo previews and portfolio proofs, precisely because it can't be trimmed off without also cutting the photo's subject. A corner placement is less intrusive and better suited to attribution — a website URL or handle in the bottom corner that doesn't interfere with viewing the image, at the cost of being easy to crop out.

Lower opacity (15–25%) keeps the underlying image easy to view — appropriate when the goal is attribution rather than deterrence. Higher opacity (40%+) makes the mark harder to ignore or edit around, more appropriate for a sample image not meant to be used as-is.

Privacy: what happens to your image

The watermark is drawn directly onto the image using the Canvas API, entirely in your browser — the photo is never uploaded. Open DevTools → Network while using the tool and you'll see no outbound requests.

Frequently asked questions

Is my image uploaded anywhere?
No. The watermark is drawn directly onto the image using the Canvas API in your browser. Nothing is sent to a server.
Can I use a logo image as the watermark instead of text?
Not with this tool — it applies a text watermark only. For overlaying a logo image, keptlocal's Add Image to PDF tool serves a similar purpose for PDF pages; for photos specifically, layering a logo currently requires an image editor.
Does the watermark work on transparent PNGs?
Yes — the watermark is drawn on top of the existing image content, transparency included, and the output preserves the original format's transparency support.
Will the watermark reduce my image's resolution?
No — the output keeps the original image's pixel dimensions. Only the watermark text is added; nothing about the underlying image is resized or recompressed beyond the normal encoding step of saving a canvas back to an image file.
What opacity should I use?
20–30% keeps a mark visible without seriously obscuring the photo underneath — the common choice for portfolio previews and proofs. Higher opacity (40–60%) suits situations where discouraging unauthorized use matters more than the photo staying easy to view, like a sample image meant to be replaced after purchase.