Resize PDF pages to A4, A3, Letter or custom dimensions

1 min read·25 July 2026

Need to convert a US Letter document to A4, or scale an A3 design down to A4 for printing? PDFrust lets you change the page size of any PDF while keeping content proportional.

Page size vs. scaling

Changing page size is not the same as scaling. When you resize the page, you change the paper dimensions. Content can be scaled to fit or cropped, depending on your choice. The resize tool offers both options.

Available paper sizes

ISO formats: A3 (297 × 420 mm), A4 (210 × 297 mm), A5 (148 × 210 mm). US formats: Letter (8.5 × 11 in), Legal (8.5 × 14 in). You can also enter a custom size in millimetres or points.

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Portrait vs. landscape

Set orientation alongside the size. To flip individual pages between portrait and landscape, use the rotate tool per page rather than the resize tool.

For print production

Print shops often require specific page sizes including bleed and trim marks. Always check the exact specifications before resizing. Avoid additional compression after resizing if the document is destined for professional printing.