Add page numbers
Number the pages of a PDF. Drop as many files as you like.
Runs on your device. The file is never uploaded.
Add page numbers stamps every PDF page 24 points up from the bottom edge, centred, in Helvetica at size 10 by default. The count starts at 1 unless you set another whole number, and each file restarts from that value. The label is always decimal, so there is no way to stamp roman numerals or letters.
Questions
Where does the number go on the page?
Bottom centre, 24 points up from the foot of the page, horizontally centred by measuring the text width. There is no position setting: that is one place, deliberately. The number is drawn in Helvetica, in black, at the font size you set, which defaults to 10.
Can I start from a number other than 1?
Yes. The start setting is the number given to the first page, and every page after it counts up by one. It accepts any whole number, including zero and negatives, and rejects anything else with "start must be a whole number". There is no way to skip pages or restart the count partway through.
Does it upload the PDF or need an account?
Neither. pdf-lib loads your file, draws the numbers and saves it again, all inside a Web Worker in this tab. No request goes out while it runs, and there is nothing to sign in to. The file you download was built on your own machine from the bytes you dropped in.
Can I number a whole batch at once?
Yes. Drop as many PDFs as you like and each is handled separately, coming back as its own file with a -numbered suffix. Each file restarts at your start value rather than continuing across the batch. If you want one run of numbers spanning several documents, use Bates numbering instead.
What if there is already content at the bottom of my page?
The number is drawn over it. Nothing is erased, no white box is painted behind the text, and no space is added to the page, so a footer that already sits at the bottom centre will collide. Check the first page of the result before you run a long document.
How is this different from PDF page labels?
This one paints ink onto the page, so the numbers are part of the printed document. Page labels change the label your reader shows in its page box and thumbnails, and draw nothing at all. Use this for something you are printing and page labels for something you read on screen.