Try it now

The watermark tool runs the same browser-local engine described on this page.

Open the Watermark tool

Why this matters

A cloud watermarker handles the unwatermarked source, which is exactly the version that should not be exposed. The point of watermarking is often that the watermarked output is OK to share but the source is not.

Browser-local watermarking inverts this. The source stays on your laptop, the overlay is applied in browser memory, and the watermarked output is downloaded to your disk. The unwatermarked version was always only on your machine; the watermarked version is the only artifact that gets distributed.

What you actually get

Logo or text overlay

Add a PNG/SVG logo or a text watermark in any position, with opacity and size controls. The overlay is applied during a local FFmpeg re-encode.

Source file never seen by us

The unwatermarked source stays in your browser. The watermarked output is the only file that leaves your machine, going to your downloads folder, then to wherever you choose to share it.

Position presets and custom coordinates

Corner positions (top-left, top-right, bottom-left, bottom-right, center) cover most cases. Custom X/Y coordinates work for specific brand-style requirements.

Works for batch-style workflows

Each video is processed independently. Drop one, watermark it, download, drop the next. No state carries between jobs.

How to watermark a video privately

01 Open the Watermark tool

Load the page below. FFmpeg WebAssembly handles the overlay locally.

02 Drop the source video

Drag the unwatermarked video in. The browser reads it from disk.

03 Add the watermark

Upload a logo image or type a text watermark. Set position, size, and opacity.

04 Watermark and download

Run the watermark pass. The marked MP4 is saved to your downloads folder.

Frequently asked questions

Why is watermarking privacy-sensitive?

Because the unwatermarked version is often the one that should not be shared. The whole point of adding a watermark is that the watermarked output is the safe-to-share version. A cloud watermarker sees the pre-watermark file, which is the wrong version to expose.

Can I add my own logo, or only a text watermark?

Both. Logos accept PNG or SVG files; text watermarks let you type any string. Opacity, position, and size are configurable for both.

Does the watermark survive social media re-encoding?

Yes. Burning the watermark into the video frames (rather than overlaying it as metadata) means it stays visible on TikTok, Instagram, YouTube, and anywhere else that re-encodes uploads. The watermark is part of the pixels.

Can I add multiple watermarks to one video?

One overlay per pass. For multiple watermarks (e.g., logo in one corner and text in another), run the watermark pass twice with different inputs.

Will the watermark slow down the encoding?

A small amount. Watermarking is a filter applied during re-encoding; the overhead is in the order of 10-20 percent extra encoding time, depending on watermark complexity.

Related Tools and Resources

Watermark Video

The actual watermark tool.

Private Video Editor

Full editor with text overlays and timeline watermarking.

Private Video Trimmer

For trimming the source before watermarking.

Private Video Compressor

For shrinking the watermarked output before sharing.