Calculator
What the Add Page Numbers to PDF does
Add Page Numbers to PDF: draws a page number on every selected page in Helvetica at the position, size and margin you choose, with formats such as "Page 3 of 12". Everything runs in your browser and the file is never uploaded.
Drop in a file and the Add Page Numbers to PDF handles it locally. Everything runs on your own device, which means no waiting and no copy left on a server.
Most people who open the Add Page Numbers to PDF are people preparing a file to send. Uploading a document to an unknown server is exactly what you should avoid with anything private.
The document is read into memory by your browser and never uploaded, so private paperwork stays private.
The field reference, the method and a worked example using the default inputs follow the tool itself.
What do the Add Page Numbers to PDF fields mean?
The Add Page Numbers to PDF uses 7 inputs. The page opens in a usable state: real values in, real answer out, ready to edit.
| Field | What to enter | Default |
|---|---|---|
| PDF File | stays on your device | none |
| Position | choose from Bottom centre, Bottom right, Bottom left, Top centre, Top right or Top left | Bottom centre |
| Format | choose from 1, 2, 3, Page 1, Page 1 of N, 1 / N or - 1 - | 1, 2, 3 |
| Start numbering at | accepts 0 to 9999 | 1 |
| Font size | measured in pt; accepts 6 to 48 | 11 |
| Margin from edge | measured in mm; accepts 0 to 60 | 12 |
| Pages (all, or e.g. 2-10) | required | all |
How does the Add Page Numbers to PDF work?
Each output is derived from the inputs above in a single pass; there is no hidden state carried between runs, so the same inputs always give the same conversion.
Bad input produces an error, never a confident-looking wrong answer.
What a typical run looks like
You provide: PDF File, Position, Format, Start numbering at, Font size, Margin from edge and Pages (all, or e.g. 2-10)
What happens: the file is read into memory by your browser, processed locally, and offered back as a download. It is never uploaded.
You get back: the output file, and a status line reporting what the tool read and wrote.
A fast machine finishes sooner than a slow one, and the only ceiling on file size is the memory available to the page.
How to use it
- Choose your file under PDF File, or drag it onto the drop area.
- Pick a value for Position: the options are Bottom centre, Bottom right, Bottom left, Top centre, Top right or Top left.
- Pick a value for Format: the options are 1, 2, 3, Page 1, Page 1 of N, 1 / N or - 1 -.
- Enter Start numbering at (0 to 9999).
- Set Font size in pt (6 to 48).
- Put Margin from edge in mm (0 to 60).
- Key in Pages (all, or e.g. 2-10).
- Press Add Numbers.
- Read Status, Pages numbered and First label in the results panel.
- Copy Link when you want to return to this exact configuration; Print when someone needs it on paper.
What this tool does not do
- Encrypted or password-protected files must be unlocked before they can be processed.
- Very large documents are limited by your device memory, not by a server quota.
- It will not warn you that a different tool would suit your question better.
- A plausible-looking answer from the wrong input is still the wrong answer: verify the fields first.
- Performance scales with your own hardware, since no server does the work.
Frequently asked questions
Enter Font size in pt and Margin from edge in mm. Each field states its unit next to the input, and outputs are labelled the same way.
Start numbering at accepts 0 to 9999. The range is enforced before the calculation runs, so a bad entry never reaches the formula.
No upload takes place. The file is handled entirely in the browser and discarded when you close the tab.
No charge. Everything on the page is available without signing in.
The computation is exact; how much you should trust the answer depends on how good your inputs are.