Make room round the edges of a finished document for a binding, for margin notes or for the guillotine.
Add Margins to PDF
Make room round the edges of a finished document for a binding, for margin notes or for the guillotine.
The PDF is opened, measured and rewritten inside this browser tab. Pages you leave out of the selection are copied through untouched, and nothing is uploaded.
A thesis binder swallows 20 mm of the inner edge, a print shop asks for 3 mm outside the trim line, and a reviewer wants somewhere to write — and all three turn up after the document has been exported, when reopening the original layout is no longer an option. There are only two honest ways to make the room and both are here. Enlarging the page grows the sheet around the drawing and touches nothing else, so links, form fields and comments go on working exactly as they did. Keeping the paper size scales the drawing down into the margin instead and moves every annotation with it. A thumbnail shades the band being added, and the page size is quoted in millimetres before and after.
Features
Margins in millimetres, inches or points, linked together or one side at a time
A binding gutter that swaps edges by page — left on 1, 3, 5 and right on 2, 4, 6
Enlarge the page: the sheet grows and not a byte of the content is redrawn
Keep the paper size: the content scales into the margin and is centred in it
Link, form-field and comment rectangles are moved and resized with the content
All pages, odd, even, or a list such as 1-4, 9 — the rest are copied through
Margins land on the sides you see, even on pages with a quarter turn set on them
A shaded thumbnail of the page that changes, and the size in mm before and after
How to use the Add Margins to PDF
Drop the PDF onto the page
Set the margins, and any binding gutter, in millimetres, inches or points
Choose whether the sheet grows or the content shrinks to make the room
Check the shaded thumbnail, then add the margins and download
Example
Input
thesis.pdf (A4), 15 mm all round plus a 20 mm gutter, enlarge the page
Output
thesis-margins.pdf — 260 × 327 mm, the gutter on the left of odd pages and the right of even ones
Nothing on the page moved, so the cross-references still jump to the right place.
Common errors & troubleshooting
The text came out smaller than in the original. — That is "Keep the paper size" doing what it says — the drawing is scaled down to fit inside the margin. Switch to "Enlarge the page" when the printed sheet is allowed to grow instead.
A page was skipped, with a message about the margins being too wide. — Keeping the paper size needs something left between the margins, so a 60 pt margin on a 100 pt page has nowhere to go. Reduce it, or enlarge the page, which has no such limit.
The printer shrank the whole thing and added its own border. — An enlarged sheet is no longer a standard paper size, so the driver scaled it down to fit. Print at 100% or "actual size", or pick a paper size at least as big as the new page.
The new margin is the wrong colour. — The added area is empty page, so it prints as whatever the paper is. A coloured background in the original only covered the old page box — lay a full-page colour under the content with Overlay PDF to carry it into the margin.
Frequently asked questions
Which mode keeps the links in my bibliography clickable?
Both do, by different routes. Enlarging the page moves nothing at all, so every link, field and comment stays exactly where it was. Keeping the paper size scales the content, and each annotation rectangle is scaled to match, so it still sits over the right words.
Why does the binding gutter change sides from page to page?
Because the spine does. In a bound copy page 1 sits on the right, so its inner edge is the left one; page 2 faces it, so its inner edge is on the right. Alternating puts the extra width against the binding on both.
Is 3 mm of bleed the same thing as a 3 mm margin?
Not quite. Bleed is extra sheet outside the trim line for the guillotine to cut through, and artwork is supposed to run into it. Enlarging the page gives you the extra sheet, but it does not stretch the artwork out there, so anything that must bleed has to be drawn into it.
Does adding a margin re-encode the fonts and images in the document?
No. Enlarging only rewrites the numbers that describe where the page boundary is. Keeping the paper size wraps the page's existing drawing instructions in a scale, so the fonts and images inside remain the very same objects.
What happens to a page that already has a quarter turn set on it?
The margins go on the sides you actually see. A page turned 90 degrees keeps its visual top along one of its internal edges, and the extra room is added there, so "top" still means the top of the page on screen.
Related tools
Crop PDF — Trim margins from every page via the crop box.
Resize PDF — Rescale every PDF page to A4, Letter or another standard size, content centred.
PDF N-up — Print 2, 4, 9 or 16 pages per sheet, with a booklet option for folding.
Overlay PDF (Letterhead) — Lay a letterhead or background PDF under or over every page of another PDF.