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PDFページ番号付加・位置とフォーマット調整
PDFページ番号付加・位置とフォーマット調整
本ツールは100%クライアントサイド（ブラウザ内）で動作します。写真、動画、音声、PDFファイルが外部サーバーにアップロードされることは一切なく、お使いの端末のメモリ内で安全に処理されます。
コアアーキテクチャ & 計算式
Text Position = f(PageWidth, PageHeight, Margin, TextWidth, Alignment)
The placement of page numbers is calculated by combining the page's physical dimensions (width × height in PDF points, where 1 point = 1/72 inch) with a user-defined margin offset and the measured width of the rendered text string, dynamically adjusted for the selected horizontal alignment (left, center, right).
ベストプラクティスとガイドライン
- Use 'Page X of Y' Format for Legal Documents: Courts and regulatory bodies frequently require the 'Page X of Y' format (e.g., 'Page 7 of 42') to ensure completeness verification. This format immediately reveals if any pages are missing from a filing.
- Maintain Consistent Margins: Position your page numbers at least 30 PDF points (approximately 0.42 inches) from the page edge to prevent them from being clipped during physical printing or when viewed in PDF readers with narrow viewport margins.
- Choose Bottom-Center for Most Documents: The bottom-center position is the international standard for academic papers (APA, MLA, Chicago) and produces the cleanest visual hierarchy without interfering with existing headers or letterheads.
- Exclude Cover Pages When Needed: Professional documents typically start numbering from the second or third page. Use the 'Start From' parameter to offset your numbering sequence accordingly.
よくある質問 (FAQ)
Will adding page numbers alter the original content of my PDF?
No. The pdf-lib engine opens the existing PDF byte stream, overlays text annotations at the specified coordinates on each page, and serializes a new file. The original text, images, forms, and metadata remain completely untouched.
Can I number only specific pages instead of the entire document?
The current implementation numbers all pages sequentially. For selective numbering, you can combine this tool with the PDF Splitter to extract specific page ranges, number them, and then merge them back together.
What font is used for the page numbers?
The tool uses Helvetica, one of the 14 standard PDF base fonts guaranteed to be available in every PDF viewer worldwide. This eliminates font embedding issues and keeps the output file size minimal.
Is my document uploaded to any server during processing?
Absolutely not. The entire operation executes in your browser's JavaScript sandbox using WebAssembly-optimized pdf-lib. Your PDF bytes exist only in local memory and are garbage-collected after download.