What the PDF Page Size Converter does
This converter changes the page size of every page in a PDF - to A4, US Letter, A3, A5, Legal, Tabloid, B5, Executive or a custom size - and places the existing content on the new paper by scaling it to fit, scaling it to fill, stretching it, or centring it at 100 %, with an optional margin. Before you convert, it lists every page's current size, paper name and orientation.
The pages are rewritten, not rasterised: text stays selectable and searchable, vector graphics stay sharp, and links and form fields move with the content. Everything happens in your browser; the PDF is never uploaded.
How to use it
- Drop a PDF, or load an example. The table immediately shows each page's size in millimetres and inches, its paper name and orientation.
- Choose the new paper size, or Custom to type a width and height in millimetres, inches or points.
- Choose how the content should be placed. Scale to fit is the safe choice: nothing is cut off. Add a margin if a printer clips the edges.
- Select Resize pages, check the preview of the first pages, and download the resized PDF.
Reading the results
Scale to fit shrinks or enlarges each page by the same factor in both directions until it just fits the new paper, then centres it. When the shapes differ - US Letter is wider and shorter than A4 - there will be a white band on two sides. Scale to fill uses the larger factor, so the page covers the paper completely and the overflow on two sides is cropped.
Stretch scales width and height separately so the content covers the page exactly. It distorts circles and letter shapes when the proportions differ, so use it only for near-identical sizes. Do not scale keeps everything at 100 % and centres it; content outside a smaller page is cut off.
The scale column is the factor applied to each page. A page resized from US Letter to A4 with Scale to fit is printed at 97.27 %, which is why that conversion is usually invisible - and why shrinking A3 to A4 (about 70.7 %) makes small print hard to read.
With Match each page, the new size is turned to match each page: landscape pages get landscape paper. Pages rotated with the PDF's Rotate setting are treated as they appear on screen.
Worked example: US Letter to A4, and A4 to US Letter
The report example has two US Letter pages (216 x 279 mm, 612 x 792 points). Converting to A4 (595.28 x 841.89 points) with Scale to fit gives scale = min(595.28 / 612, 841.89 / 792) = min(0.9727, 1.0630) = 0.9727, so the content is printed at 97.27 %. It is then 595.28 points wide - exactly A4's width - and 770.36 points tall, leaving (841.89 - 770.36) / 2 = 35.8 points, about 12.6 mm, of white space at the top and bottom.
The form example goes the other way: an A4 page to US Letter. Now scale = min(612 / 595.28, 792 / 841.89) = min(1.0281, 0.9407) = 0.9407, so the page is shrunk to 94.07 %. It becomes 560.0 points wide and exactly 792 points tall, with (612 - 560) / 2 = 26 points, about 9.2 mm, of white space at each side. The form fields are scaled and moved with the page, so they still line up with their labels.
Formulas and scoring rules
- Fit scale
scale = min((W - 2m) / w, (H - 2m) / h)w, h: the page's visible size; W, H: the new paper; m: margin. Fill uses max() instead of min().- Centring offset
dx = m + ((W - 2m) - w x scale) / 2The same for the vertical offset with heights. Sizes are in points: 1 inch = 72 points, 1 mm = 72 / 25.4 points.- Paper sizes
A4 = 210 x 297 mm = 595.28 x 841.89 pt; US Letter = 8.5 x 11 in = 612 x 792 ptPaper names are matched within 2 points (about 0.7 mm).
Limitations: what the result does not prove
- Password-protected (encrypted) PDFs are refused, because rewriting them would break their protection. Remove the protection first and keep a copy.
- Pages are placed on new paper; nothing is reflowed. Changing A4 to A5 halves the area and makes text about 71 % of its size - the tool cannot rewrap text to the new width.
- Crop, bleed and trim boxes are removed, so print production marks based on them are lost. For professional print jobs, resize in the layout application instead.
- Digital signatures become invalid, because the pages change. Page thumbnails embedded in the file are dropped.
- A few malformed PDFs use drawing state that leaks between pages or content streams. The rewrite wraps each page in its own graphics state, which is correct for valid files; check the preview.
Privacy: where your data goes
Everything you paste, type or drop is processed in this browser tab. It is not uploaded, logged, stored or sent to analytics. Session recording and tag-manager scripts are switched off on this page.
Standards and sources
- ISO 216 paper sizes (A and B series) - checked 19 Sep 2026
- ISO 32000-2 (PDF 2.0) - PDF Association resources - checked 19 Sep 2026
- ISO 32000-2:2020 PDF 2.0, section 14.11.2 Page boundaries and 8.4 Graphics state
- Adobe - PDF Reference, sixth edition (PDF 1.7), section 4.2 Coordinate systems
Frequently asked questions
How do I change a PDF from Letter to A4?
Drop the PDF here, choose A4 and Scale to fit, and select Resize pages. Each page is scaled to 97.27 % and centred, which keeps all content and leaves a narrow white band at the top and bottom. Download the result; text stays selectable.
Will resizing make my PDF blurry?
No. The pages are not turned into images; the tool changes the page size and adds a scaling instruction to each page's drawing commands. Text and vector graphics stay sharp at any zoom. Photos keep their original pixels, so they print at a slightly different resolution.
What is the difference between fit and fill?
Fit makes the whole page visible, adding white space on two sides when the paper shape differs. Fill makes the content cover the whole page, cutting off a little on two sides. Neither distorts the content; Stretch does.
Why is there white space at the top and bottom after converting to A4?
A4 is taller and narrower than US Letter. Scaled to fit A4's width, a Letter page is 770 points tall on an 842-point page, which leaves about 12.6 mm above and below. Use Scale to fill if you prefer to crop the sides slightly instead.
Can I print an A4 PDF on US Letter paper without cutting anything off?
Yes: resize to US Letter with Scale to fit. The page is shrunk to 94.07 % so its full height fits, leaving about 9 mm of white space at each side. Printers' own shrink-to-fit option does the same at print time.
Do links and form fields still work?
Yes. Their rectangles are moved and scaled with the content, so a link still covers its text and a form field still sits in its box. Field values and settings are unchanged.
Is my PDF uploaded to a server to be resized?
No. The file is parsed and rewritten by JavaScript on this page, and the preview is drawn by a copy of pdf.js served from this site. Nothing leaves your browser.
Last reviewed by the A2Z.Tools team against the sources listed above.
