PDF Watermark and Page Numbers は何をしますか？
PDF Watermark and Page Numbers はブラウザ上でデータやファイルを変換するツールで、結果と制限を明確に示します。 検証済みの機能： Unicode watermark text, Adjustable size and opacity, Page N of total labels, Local PDF export.
A visible watermark is not secure redaction
Use this tool to label drafts, review copies, or ownership visibly. Do not use it to hide confidential content: the original page objects remain in the PDF, and a determined editor may be able to remove an overlay.
使い方
- Open one unencrypted PDF no larger than the 100 MB browser limit.
- Enter up to 60 watermark characters, choose a size and opacity, and enable or disable Page N of total labels.
- Select Process, review the page count and output size, then download watermarked.pdf.
実際の入出力例
Mark a twelve-page review copy
入力
Source: draft.pdf (12 pages)
Watermark: INTERNAL REVIEW
Size: 48
Opacity: 0.20
Page numbering: enabled出力
watermarked.pdf
Diagonal watermark on every page
Bottom labels: Page 1 of 12 … Page 12 of 12Text is rendered to a transparent image in the browser, which permits Unicode characters supported by the local system fonts before the image is embedded into each page.
一般的なエラーと対処
| 症状 | 原因 | 対処 |
|---|---|---|
| The PDF cannot be processed. | It is encrypted, damaged, incomplete, or not actually a PDF document. | Use an authorized unlocked copy or export a valid PDF before adding overlays. |
| The watermark is hard to read or covers important content. | Its size or opacity is inappropriate for the page design. | Reduce opacity for dense documents or adjust the size and process the original again. |
Important behavior of PDF Watermark
このツール固有の制限： The watermark is an ordinary visible PDF overlay, not tamper-proof rights management or secure redaction.
標準と実装の参考資料
- pdf-lib documentation (opens in a new tab)Documents the browser-side PDF loading, PNG embedding, opacity, rotation, and save operations used by this workflow.
- MDN — HTMLCanvasElement.toBlob() (opens in a new tab)Documents the local transparent PNG generation step used for Unicode overlay text.
PDF Watermark — FAQ
Does the PDF Watermark upload my input?
No. Processing runs in the current browser tab, and the page does not send tool input to a KitLumi processing endpoint.
What input does the PDF Watermark accept?
It accepts one unencrypted PDF, optional watermark text, size and opacity settings, and a page-number choice. The workspace checks the input and reports malformed or unsupported values before it produces a result.
What does the PDF Watermark produce?
It produces a downloadable PDF whose existing pages include the selected overlays. Copy and download controls appear when the output format supports them.
What limitation should I know?
The watermark is an ordinary visible PDF overlay, not tamper-proof rights management or secure redaction.
更新内容
実質的な更新： PDF Watermark: Added Unicode watermark text, Adjustable size and opacity, Page N of total labels, Local PDF export, responsive controls, explicit runtime disclosure, and task-specific examples and limitations.