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Công cụ này làm gì

This rebuilds a document on a different sheet size. Fit scales each page's content to the new sheet, so nothing is lost and the type gets smaller or larger with it. Crop keeps the content at its original scale and changes the paper around it, so nothing is rescaled and anything outside the new box is cut away. The content is placed as vector artwork, so text stays text and images keep their resolution either way.

Two situations account for most of it. A document made for one market's paper turns up in another - a Letter file that has to print on A4, or the reverse - and the printer either refuses it or shrinks it unpredictably. Or a poster, drawing or spreadsheet export arrives at A3 and needs to be readable on an ordinary sheet.

Cách hoạt động

1. Drop the PDF onto this page.
2. Choose the target size, or pick Custom and type the width and height in millimetres.
3. Set the orientation. Keep follows whatever shape each page already has, so a document mixing portrait text with landscape tables stays sensible.
4. Choose Fit to scale the content onto the new sheet, or Crop to leave it at full size and trim the sheet around it.
5. Press Resize and the download starts on its own.

Fit and Crop are the whole tool, and choosing the wrong one is the usual complaint about resize tools elsewhere. Fit measures the page against the new sheet, scales it by whichever dimension is tighter, and centres it - so an A4 page onto A5 comes out at 71 per cent of its size, entirely intact and harder to read. Crop draws the page at its original scale on the new sheet and centres it, so the type stays exactly the size it was and whatever falls outside the sheet is gone.

Sizes are entered in millimetres because that is how paper is sold, and converted to points on the way in - a PDF has no notion of millimetres at all, only of 1/72 of an inch. A4 is 210 by 297 mm, Letter is 216 by 279, and the custom fields accept anything from 10 mm to 2000 mm, which covers a business card at one end and a plotter drawing at the other.

Orientation is decided per page rather than for the document. With orientation on Keep, a page currently wider than it is tall gets the target size turned landscape, and an upright page gets it upright. That is what stops a report with a few landscape tables coming out with those tables squeezed into portrait sheets.

The page range under advanced options selects which pages are resized, and the output contains only those pages - it is a selection, not a filter that leaves the rest alone. Use it when you want the selected pages on a new size as a document of their own, and leave it empty for the ordinary case of resizing everything.

Each page is drawn onto its new sheet as artwork, which keeps the content vector and the text selectable but does not carry annotations across. Everything happens with pdf-lib in your browser, so a set of confidential drawings is re-sheeted without anything being uploaded.