~/tools/image-watermark

Image Watermark

Add a "For XX use only" protective watermark to ID cards, passports, diplomas, and more. Tiled layout prevents cropping. Everything runs locally in your browser.

canvas · fillText

$Drop photos here (multiple supported)

Drop ID front/back or multi-page documents at once. All processing stays local—files never leave your device.

Files never leave your device
JPGPNGWebP
01Drop photos

Multiple files supported; front and back of IDs in one go. No uploads.

02Pick a template

Apply a "For XX use only" template, then tweak layout, style, and expiration.

03Generate locally

Canvas burns the watermark locally. Download one by one or as a zip.

//Related Image ToolsAll tools

Add a Watermark to Photos Online

Local · No uploads

A watermark tool built for sensitive documents: ID cards, passports, diplomas, and bank cards. Add text like "FOR [COMPANY] VERIFICATION ONLY" in a tiled, angled pattern that covers the whole photo — crop out any part and the watermark survives. Switch to a single positioned watermark when you prefer a cleaner look. Adjust font size, opacity, rotation, and color, and append a validity date. Photos are processed locally in your browser — never uploaded — with batch zip download supported.

How to Watermark a Photo

  1. 1

    Drag in one or more photos (front and back of an ID at once is fine) — everything stays local

  2. 2

    Tap a text template to fill in "FOR [COMPANY] USE ONLY" and replace the placeholder with the real name

  3. 3

    Adjust the layout (tiled / single), font size, opacity, color, and validity date as needed

  4. 4

    Click Generate — the live preview is exactly what you get. Download individually or as a zip

Common Uses

  • Protect ID card and passport photos before sharing them with landlords, banks, or HR
  • Mark diploma and certificate photos used for online applications or verification
  • Safeguard bank card photos submitted for account verification
  • Any photo that needs a "for this purpose only" notice

Things to Keep in Mind

  • The current version supports text watermarks only — no logo image overlays yet
  • A watermark raises the bar against misuse but can't technically prevent someone from re-photographing the screen
  • Keep opacity at 15% or higher — a watermark that's too faint provides little protection

How to Choose a Photo Watermark Tool

  • vs. upload-based watermark tools: your photos never leave the device — zero exposure for sensitive documents
  • vs. your phone's built-in watermark: full control over text, position, density, and validity date
  • vs. watermarking in messaging apps: no app install, runs in the browser, batch processing included

How Photo Watermarking Works

  • Watermarks are drawn pixel by pixel on a browser Canvas: the image is decoded into a canvas, globalAlpha sets the opacity, the coordinate system is rotated, then fillText renders the text. The final export bakes the watermark into the pixels — it's not a layer, and it can't be stripped separately.
  • Tiled mode generates a staggered grid inside the rotated coordinate system — adjacent rows are offset by half a step, and the coverage radius is the diagonal length, so the corners stay covered after rotation. Crop out any region and the watermark remains intact on the rest.
  • Font size is calculated as a percentage of image width, so the watermark looks proportionally identical across photos of different resolutions. Output format follows the source (PNG keeps transparency; JPEG gets a white background), and EXIF-oriented portrait photos are automatically straightened.

Photo Watermark FAQ

Are my ID photos uploaded to a server?

No. Watermarks are drawn entirely in your browser's Canvas — your photos never leave your device. That makes this the safest way to handle sensitive documents like ID cards and passports.

What text should the watermark say?

A common format is "FOR [COMPANY / BANK / PLATFORM] VERIFICATION ONLY" — tap a template to fill it in. Naming the exact purpose limits how the photo can be reused and helps if it's ever misused.

Why add a validity date?

A note like "VALID THROUGH [DATE]" limits how long the photo can be used — after that date, the copy the other party holds expires. Common for rentals, account openings, and similar situations.

Tiled or single watermark — which should I use?

For protection, go tiled: the angled pattern covers the entire image, and cropping out a portion leaves the watermark on what remains. A single watermark looks cleaner and suits lightweight uses like copyright credits.

Can I watermark multiple photos at once?

Yes. Drag in several photos (front and back of an ID, for example), configure once, and generate for all of them — download individually or as a zip.

Can the watermark be removed?

It's baked into the image pixels, so it can't be deleted like a separate layer. That said, no watermark fully prevents someone from re-photographing a screen — still be careful about who you share sensitive documents with.