PDF 調整尺寸

直接在瀏覽器中將 PDF 頁面尺寸更改為 A4、Letter、Legal 或任意自訂大小。

將 PDF 拖曳至此處，或點擊選擇檔案

選擇 PDF 檔案

最大檔案大小：128 MB

所有處理均在瀏覽器本機完成，您的檔案不會上傳到任何伺服器。

Resize PDF to Letter Size — US 8.5×11" Standard Format

Convert any PDF to US Letter (8.5×11 inches) for submission to American institutions, US Postal Service bulk mail, or government forms. Browser-side processing, batch mode, layout preservation. Free, no upload, no sign-up — runs entirely on your device.

100% FreeNo UploadNo Sign-upUS Standard 8.5×11

使用步驟

Drop Your PDF: Drag PDFs in (any current size — A4, Legal, A3, custom). The tool shows the original dimensions and the target difference at a glance.
Pick Letter: Select 'Letter (8.5×11 in)' as the target. Preset also includes Legal, A4, A3, A5. Choose 'Fit' (proportional, recommended) or 'Stretch' (force-fit, may distort).
Resize: Click 'Resize to Letter'. Every page is reprocessed to Letter dimensions in your browser. Aspect ratio is preserved automatically. A 50-page PDF completes in 5-10 seconds.
Save: Download the resized PDF. Compatible with US Letter paper, US Postal Service automated processing, US government form portals (I-9, W-9, SF-86). Open in any reader or print directly without scaling.

為何選擇此工具

100% Local Processing: Files are processed entirely in your browser using JavaScript — never uploaded to any server.
No Limits: No file count or file size restrictions. Process as many files as your device can handle.
No Sign-up: Free forever, no account needed, no email required. Open the page and start.
Private by Design: Nothing is sent to any server. Close the tab and your files are gone forever.

常見問題

How do I make a PDF Letter size?

Drop your PDF into our PDF Resize tool, select 'Letter (8.5×11 inches)' as the target size, click 'Resize'. The PDF downloads with all pages resized to Letter dimensions. Runs entirely in your browser, no upload needed.

Why does my PDF need to be Letter size?

Many US institutions require Letter: IRS tax forms, federal job applications (SF-86, I-9), USPS bulk mail, legal filings, university admissions, US court documents. International or A4-sized PDFs may be rejected or need to be reprinted. Resizing once makes them universally compatible.

Will the content look squished after Letter resize?

No — by default we use 'Fit' mode, which preserves aspect ratio. Content scales proportionally to fit the new dimensions. For PDFs already near Letter size, the visual change is minor. For A4-sized PDFs (slightly taller than Letter), content scales down a few percent — barely noticeable.

Can I do the reverse — Letter to A4?

Yes. Use the same tool, but pick 'A4 (210×297 mm)' as the target. We handle all common sizing conversions: A4↔Letter, A3↔A4, Letter↔Legal, and custom dimensions. Useful for international submissions where A4 is required.

Will my PDF be uploaded?

No. Everything happens locally via pdf-lib. Your PDF and the resized output stay on your device — useful for confidential documents like financial records or legal filings.

Can I resize multiple PDFs at once?

Yes — drop several PDFs and our batch mode processes them sequentially. You get a ZIP of all resized PDFs. Each processes independently, so a 5-document batch takes about the same time as 5 individual conversions.