Add page numbers to a PDF in your browser, with the number each page will actually carry shown on the page itself before you download. The tool measures the corner it is about to print in and tells you which pages already have something there — the collision every other numbering tool leaves you to discover on paper.
Step by step
01Add the document
Drop a PDF anywhere on the page. It is read into this tab and never uploaded, and the file you chose is never modified — what you download is a new copy.
02Choose the format and where it sits
Plain digits, 'Page 3', '3 of 12', dashes, or lowercase roman for front matter. Six positions: three across the top, three across the bottom. Each page in the grid shows the number it is going to receive.
03Say which pages are exempt
Set the first numbered page to leave a cover and contents alone, and skip individual pages or ranges for plates and inserts. The count carries on past a skipped page rather than restarting.
04Read the collision check, then download
Pages already carrying something in the chosen corner are marked 'occupied' in the grid and listed under Checks. Move the number to another corner, or accept the overlap knowingly.
Worked example
The case that produces the complaint. A twelve-page report has a running footer on its body pages, a cover, and a contents page — and 'add page numbers' quietly prints on top of the footer.
Given
What the tool reports before anything is downloaded
Numbered 10 of 12
Reads Page 1 of 10 … Page 10 of 10
Already printed there 10 pages <-- the running footer
Suggestion bottom-right is clear on all 12Two things go wrong here and both are silent. The total counts numbered pages, not pages in the file — 'Page 1 of 12' on the third sheet is wrong. And bottom centre is exactly where the footer already is.
Why this one
The denominator counts numbered pages
'Page 3 of 12' on a document whose first two sheets are unnumbered front matter is wrong, and readers notice. When you exclude pages from numbering, the total shrinks to match — ten numbered pages read 'of 10', not 'of 12'.
The corner is the reader's, not the file's
A PDF page can carry a rotation the viewer applies at display time, so its stored width and height are not what you see. A number placed from the stored box lands on the left edge of a page turned 90 degrees. Every position here is computed in the frame you are looking at and mapped back, and the text is turned to match so it still reads horizontally.
Mixed page sizes do not drift
One document with an A4 body and a Letter appendix has two different page heights. An offset measured once and reused walks up the page at the boundary, so every position is recomputed from each page's own box — including pages whose box does not start at the origin, which is what cropping and imposition leave behind.
The collision check is a measurement
Before anything is written, the corner about to be printed in is rasterised and its ink is measured on every page. A page counts as occupied above about 1.5% coverage in that strip — high enough to ignore scanner grain, low enough to catch a one-line footer. No other page-numbering tool reports this, which is why the overlap is usually discovered after printing.
Skipping keeps the sequence
A skipped page keeps its place in the document but takes no number, and the count continues past it. That is what you want for a full-bleed plate in the middle of a chapter: the plate is unnumbered, and the page after it is one more than the page before.
The judgement call
The defaults suit a plain document. These are the cases where they do not.
A report with a running footer
Bottom right or top right
A centred footer and a centred number collide. The outer corner is almost always free, and the check will confirm it before you download.
Something that will be bound or hole-punched
Keep 28pt or more
Binding eats the inner edge and a punch takes about 12mm. A number under 18pt from the edge can also fall inside a laser printer's unprintable border and simply not appear.
Front matter before the body
Roman, then a second pass
The printing convention is roman for front matter and arabic from the first body page. Number the front matter as roman, download, then run the result again starting at the body page.
A scanned document that came out sideways
Straighten it first
The number is placed in the corner the reader sees, so it will be right — but it will be right on a page that is still sideways. Rotate first, then number.
A document that must not change
Do not number it
Stamping rewrites the file. A digitally signed PDF's signature will not survive it, and for evidence or filing the copy is no longer the original.
Reference
FAQ
No. The document is read, measured and rewritten by this page, on your own machine. Nothing is sent anywhere, there is no account, no page limit and no watermark — and the tools keep working with the network disconnected, which is the quickest way to check the claim.
Set 'First numbered page' to 3. Pages 1 and 2 are left untouched, and the count starts at whatever 'Start the count at' says — leave it at 1 and the third sheet reads 1. The 'of N' total also drops to the number of pages that actually carry a number.
Yes, choose the roman format — it prints lowercase i, ii, iii, which is the convention for front matter. A document that needs roman front matter and arabic body is two passes: number the front matter as roman, download it, then run that file again with the body's first page as the start.
The tool tells you before you download. It measures the ink already sitting in the corner it is about to print in, on every page, and marks the ones that are occupied both in the grid and under Checks. If bottom centre is taken, bottom right is usually clear.
Nine to eleven points is the usual range for a document read on paper, against a body size of ten to twelve. The margin matters more than the size: keep the number at least 18pt from the edge, because most laser printers cannot print closer than about 5mm and a number placed under that simply disappears.
Yes. A digital signature covers the bytes of the file, and stamping rewrites them, so the signature will no longer validate. Number the document before it is signed.
Because the printed sequence counts numbered pages, not sheets. If you excluded a cover and a contents page, the fourth sheet carries the number 2. That is the intended behaviour, and it matches how a printed book is numbered.
Keep going
Merge PDF
Combine documents first, then number the result once so the sequence runs across the whole thing.
Rotate PDF
Straighten a scan before numbering it, so the number lands on a page the right way up.
Split PDF
Cut a numbered document into parts, at its bookmarks or by range.
Extract PDF pages
Pull the pages you need out of a document by clicking them.