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Add a watermark to JPG

JPG の画像に名前やロゴを重ねます。

要点

To watermark a JPG, upload it to ezimagetools.com, type the text you want stamped on it or upload a logo, then set the position, size and transparency. Tiling repeats the mark across the whole picture, which is far harder to crop out than a single corner mark. A watermark on a JPG is permanent — the pixels themselves are rewritten, so there is no layer to switch off later. Free, and no account is needed.

概要

対応形式
JPG files, plus a PNG logo if you are using one
出力
The same JPG with the watermark permanently applied
最大ファイルサイズ
1 ファイルあたり 50 MB
一度に処理できる数
一度に最大 20 件
料金
無料。処理できる枚数に上限はありません
アカウント
不要です。登録は一切ありません
ファイルの削除
処理から 1 時間以内に自動削除

更新日 2026-08-31

jpg に透かし方法

  1. Add your JPG

    Tap the upload box and choose the JPG you want to protect.

  2. Write your mark

    Type the text, or upload a logo. A PNG logo with a transparent background works best.

  3. Place it

    Choose a corner or the centre, set the size and transparency, or switch on tiling to repeat it.

  4. Apply and download

    Press Watermark, then save the marked JPG.

What a JPG is

JPG (also written JPEG) is the format almost every camera and website uses. It saves space by discarding the detail your eye is least likely to notice, which is why it cannot store transparency and why every re-save costs a little quality.

A watermark is a deterrent, not a lock

A visible mark makes casual reuse obvious and inconvenient, which is most of what it is for. It will not stop someone determined to edit it out. If the picture must not be copied at all, do not publish it at full resolution.

よくある質問

Why watermark a JPG?

A watermark on a JPG is permanent — the pixels themselves are rewritten, so there is no layer to switch off later. Keep the unmarked original somewhere before you start.

How do I stop someone cropping my watermark off?

Switch tiling on. A single mark in a corner takes one crop to remove; a mark repeated across the whole picture cannot be cropped out without destroying the image. Keep the transparency moderate so it is visible but not ruinous.

Can I use a logo instead of text?

Yes. Upload a PNG with a transparent background and it is placed exactly like a text mark — same positions, same size and transparency controls. A JPG logo will bring its own white box with it, which is why PNG is the right format for this.

Is the watermark permanent?

Yes. The pixels of the JPG are rewritten, so there is no layer anyone can switch off. Keep a copy of the unmarked original before you start — we do not keep one for you.

Does watermarking change the size of the picture?

No. The width and the height stay exactly as they were; only the pixels under the mark change. The file size shifts a little because the picture itself has changed.

Is it safe to watermark JPG files online?

Yes. Your file is processed on our server and deleted automatically within one hour. We never look at it and you do not need an account.

Your images are processed on our server and deleted automatically within one hour. We never look at them and you do not need an account.

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