Is the original text still selectable afterwards?

Yes. The number is drawn on top of the existing page content as text; the page is not turned into an image. Your document keeps its searchable, selectable text and is not re-compressed.

What does the margin figure mean?

It is the gap between the number and the edge of the page, measured in points (72 points = 1 inch, about 2.54 cm). A margin of 36 is half an inch. Increase it if the number feels too close to the edge or sits over a footer.

Will the number clash with anything already on the page?

If a page already prints its own number in the same corner, the two will overlap — the tool draws on top and does not detect existing content. Choose a different corner or a larger margin, and check the result before sharing it.

How do I add page numbers to a PDF?

The tool stamps a page number on every page at the position, size and starting number you choose, then gives you the numbered PDF to download. It works on the existing pages, so nothing is rasterised and the text in your document stays selectable.

Runs entirely in your browser · no upload · no account · no watermark

Choose the PDF you want to number.
Set the position, starting number and text size.
Number it, then download the PDF.

PDF file

Choose one PDF. It is read by this page and never sent anywhere.

Use the “Page X of Y” format

What this page can do

Choose position and starting number
Optional “page X of Y” format
Adjustable text size and margin
Existing text stays selectable

When to use this page

Numbering a document you just assembled from several PDFs.
Starting the count at a page other than one, after a cover or a table of contents.
Putting a plain number in a fixed position on every page.

When to use something else

You need different numbering styles in one document (i, ii, then 1, 2) or chapter-relative numbers.
The PDF already has page numbers that need replacing — this adds a new mark on top, it cannot remove the old one.
You expect a table of contents or cross-references to update.

How it compares with other options

Word, LaTeX or an editorial tool generates page numbers as part of the document, so they stay editable, follow section styles and feed the table of contents. Here the number is drawn onto the existing page and becomes part of its content: it cannot be edited later, it will not reflow, and nothing else in the file knows it exists. In exchange you get a working number on a PDF you cannot re-export from its source.

Where your files go

Nowhere. This page loads the code that does the work, and from then on the file you open is read by your own browser. There is no upload step, no temporary server copy and no cleanup to trust — the data never crosses the network, so there is nothing to delete afterwards. You can confirm it yourself: open your browser’s network panel while the tool runs and watch it stay quiet.

Questions about this tool

Is the original text still selectable afterwards?: Yes. The number is drawn on top of the existing page content as text; the page is not turned into an image. Your document keeps its searchable, selectable text and is not re-compressed.
What does the margin figure mean?: It is the gap between the number and the edge of the page, measured in points (72 points = 1 inch, about 2.54 cm). A margin of 36 is half an inch. Increase it if the number feels too close to the edge or sits over a footer.
Will the number clash with anything already on the page?: If a page already prints its own number in the same corner, the two will overlap — the tool draws on top and does not detect existing content. Choose a different corner or a larger margin, and check the result before sharing it.