Give a PDF room to breathe: add white space to any side in millimetres, inches or points, add a binding gutter that alternates for double-sided printing, or shrink the content so the paper size stays the same. Everything runs in your browser.
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Margins
Mode
Preview
Choose a PDF to get started.
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How to use the Add Margins to PDF
Choose your PDF by dropping it on the box or clicking to browse.
Enter the margins in mm, inches or points. Keep Same on all sides ticked for an even border or untick it to set each side.
Add a gutter if the pages will be bound, stapled or hole-punched, and pick double-sided or single-sided.
Choose the mode: Enlarge pages adds the space outside the content, Keep page size shrinks the content so it still prints on the same paper.
Press Add margins & download PDF to save the new file.
Enlarge pages or keep the page size?
Enlarge pages
Keep page size
Content size
Unchanged (100%)
Scaled down evenly to fit inside the margins
Page size
Grows by the margins (A4 + 10 mm each side = 230 × 317 mm)
Unchanged (A4 stays 210 × 297 mm)
Best for
Room for notes, stamps or annotations on screen; a frame around slides
Printing on standard paper; making space for binding or hole punching
Printing
Use "Fit to page" in the print dialog
Print at 100% (actual size)
In Keep page size mode the scale factor is the smaller of (page width − left − right) ÷ page width and (page height − top − bottom) ÷ page height, so the content keeps its proportions. For example, 15 mm on every side of an A4 page gives min(180 ÷ 210, 267 ÷ 297) = 0.857, or about 86%.
Common margin and gutter sizes
Purpose
Millimetres
Inches
Points
Typical document margin
20–25 mm
0.75–1 in
57–72 pt
Non-printable edge on office printers
4–6 mm
0.17–0.25 in
12–18 pt
2- or 3-hole punch gutter
15–20 mm
0.6–0.75 in
43–57 pt
Staple or comb binding gutter
10–15 mm
0.4–0.6 in
28–43 pt
Space for handwritten notes
30–50 mm
1.2–2 in
85–142 pt
1 inch = 25.4 mm = 72 PDF points. With a double-sided gutter the extra space goes on the left of odd pages (right-hand pages in a bound book) and on the right of even pages, so it always lands on the bound edge.
Frequently asked questions
How do I add white space around a PDF?
Open the PDF, enter the margin you want (for example 15 mm), keep Enlarge pages selected and press Add margins. Each page grows by the margin on every side, and the original content stays exactly the same size in the middle.
How do I add margins without changing the page size?
Choose Keep page size (shrink content). The content is scaled down evenly and centered inside the new margins, so an A4 or Letter document still prints on the same paper. A 15 mm margin on all sides of an A4 page scales content to about 86%.
What is a binding gutter?
A gutter is extra space on the edge that gets bound, stapled or hole-punched. For double-sided printing the inside edge alternates: the left side on odd (right-hand) pages and the right side on even pages. For single-sided printing the gutter is always on the left.
How much margin do I need for hole punching or binding?
Standard 2- or 3-hole punches sit about 10 to 13 mm from the edge, so a gutter of 15 to 20 mm (about 0.6 to 0.75 in) keeps text clear. Comb and coil binding usually need 10 to 15 mm, and a perfect-bound book 12 to 20 mm depending on thickness.
Will adding margins reduce quality?
No. The tool changes the page boxes or applies a scaling transform to the existing vector content. Text remains selectable and searchable and images are not re-compressed.
Is my PDF uploaded?
No. The PDF is edited entirely in your browser with the pdf-lib library and never leaves your device.
Are all the tools on FreeToolCabin tested for quality and accuracy?
Yes! Every tool on our site undergoes automated Q/A testing in real browser environments to ensure high precision, correct output, and zero errors. If you happen to spot a bug or have a suggestion, please contact us at [email protected] and our team will review it right away.