Add Page Numbers to PDF

How does the tool work?

The tool uses a battle-tested open-source JavaScript library to add page numbers to a PDF directly in your browser. Processing is fully local — no server connection, no upload, no third party touching your file.

Technically, the tool writes a text stamp into the content stream of every page. The underlying library loads the PDF, reads each page’s size and rotation, computes the exact (x, y) position of the label in PDF points and writes the text command at the right spot. The result behaves like any other written page number — searchable in the reader, printable on any printer, copyable.

Before loading, every file is validated against the %PDF- magic header. Corrupt files or renamed non-PDFs are rejected upfront with a clear error message, before any heavy code is fetched.

How do you add page numbers in the browser?

Drop the PDF onto the dropzone or pick it through the file browser. The tool immediately shows page count and file size in the header. Four settings drive the result:

• Position — a 3 × 2 grid: top/bottom × left/center/right. Default is bottom-center, because that is the default in Word, LaTeX and Pages. Top-right is the second common choice for print layouts with a gutter on the left.
• Format — six variants:
  • 1 — just the number; minimalist, common in books
  • 1/N — fraction form; common in contracts and attachments where “please confirm no page is missing” matters
  • Page 1 / Seite 1 — language-prefixed
  • Page 1 of N / Seite 1 von N — explicit, common for official documents and authority submissions
• Font size — 8, 10, 12 or 14 points. 10 pt is the Office default, 12 pt fits textbooks, 14 pt suits print contracts.
• Skip the first page — when the first page is a cover sheet, exclude it from numbering. The count then starts at page 2 of the original.
• Start from — the first page number that appears. Default 1. If your document logically “continues” (Appendix 5 after a 124-page main matter), enter 125 here.

Click Add page numbers — the file is ready for download immediately.

How does the format picker work?

Six variants are offered because different industries use different conventions:

• 1 — bare number. The most unobtrusive form, used in novels, academic papers and print magazines.
• 1/N — fraction form with total. Standard for contracts, offers and authority submissions — the reader sees at a glance whether any page is missing.
• Page 1 / Seite 1 — language-prefixed. Used in English or German documents where the prefix is part of the visual layout.
• Page 1 of N / Seite 1 von N — explicit and language-prefixed. Standard in German administration and US tribunals.

What is missing here: Roman numerals for prefaces or appendices. That is a deliberate V1 restriction — very few users need it, and the clean solution would be a “Section” concept with separate numbering ranges. For now, the manual workflow works: number the preface as a separate PDF with i, ii, iii…, the main matter as a second PDF starting at 1, and then merge them.

Why does privacy matter for page numbers?

smallpdf, the iLovePDF workflow and the pdf24 tool all follow the same pattern: upload the file, the server adds page numbers, download the result.

“Files removed from our servers after one hour.”
— smallpdf Trust Center

“automatically deleted after 2 hours”
— iLovePDF GDPR statement

Sounds harmless. But the retention window means exactly that: your file sits on someone else’s server for those two hours. For contracts, authority submissions, medical records, payroll, patient files or job applications, that retention window is the problem, not the solution. You are delegating confidentiality to a deletion policy rather than guaranteeing it structurally.

The FBI publicly warned in March 2025 that many free PDF converters on the internet operate as malware fronts. Even without malicious intent, every server upload sends a confidential document to a third party — privacy promises are only worth as much as the operational discipline behind them.

This tool makes the upload structurally impossible. The PDF library (MIT-licensed, open source) loads into your browser tab and runs there. Your PDF travels from your disk into the browser memory, gets numbered, and lands as a download back on your disk — without the bytes ever leaving the device. No sign-up, no cookie banner for ad partners, no tracking.

How does the tool behave on rotated pages?

Some scanner apps (Adobe Scan, CamScanner, ABBYY FineReader, most office multifunction printers) write landscape pages as physically portrait pages with /Rotate 90 — the viewer rotates on display so humans see them upright.

When you apply bottom-center to such a page, the number is placed on the visual bottom edge, not the storage bottom. That is by design: the position picker tracks what humans see, not the file’s storage axis.

Mathematically the tool performs a coordinate transformation: a visual (x, y) is mapped through the rotation into a storage (x, y), and the rotation is passed to the library alongside the storage position. The drawn label therefore sits upright on the visual position — exactly where the user expects it.

Which PDF files are supported?

The tool handles every common PDF version (1.0 to 2.0). The full input behaviour:

Supported without restriction:

• Standard PDFs of any page size (A4, Letter, A5, landscape, mixed)
• PDFs with embedded fonts, raster images and vector graphics
• PDFs with interactive forms and annotations
• PDFs that already carry a /Rotate value (scanner output)
• Mixed-rotation documents — every page is handled individually
• Any number of pages — the ceiling is browser memory (~200 MB)

Handled with a hint:

• Very large files (>100 MB): a warning appears; processing may take a few seconds depending on your device

Not supported:

• Files without a valid %PDF- header (renamed non-PDFs): rejected with a clear error message
• Password-protected PDFs: rejected with a clear error message — unlock them first, then load again

What do users ask most about adding page numbers?

The most common questions about usage, privacy and the underlying mechanics:

Does my PDF get uploaded to a server?

No. All processing runs inside your browser. Your file never leaves your device — no server, no upload, no tracking.

How do I add page numbers to a PDF?

Drop the PDF, pick one of the six positions and a format. Click Add page numbers and download the result. Defaults: bottom-center, Page 1, 10 pt — matches what every Office app produces.

Can I skip the first page?

Yes. Toggle Skip the first page — numbering then starts from page 2 of the original. Handy for theses where the cover sheet must not carry a number, or for contracts with an unlabeled title page.

Can I start counting from a number higher than 1?

Yes. The Start-from field accepts any positive integer. Default is 1. If your document logically continues (Appendix 5 after a 124-page main matter), enter 125 here. If you want page 5 to be labeled Page 5 instead of Page 1, enter 5 and skip the first four pages.

What happens with password-protected PDFs?

Encrypted PDFs are rejected with a clear error message — the underlying library cannot open encrypted content. Unlock the PDF first in your PDF reader (for example Adobe Acrobat or macOS Preview) or use our PDF password remover and try again.

Which font and font size does the tool use?

A sans-serif font that ships with every PDF reader, so the file stays small and works without a font subset. Four font sizes are available: 8, 10, 12 and 14 points.

Where exactly does the number appear on the page?

Each position sits 0.5 inches (36 PDF points) from the edge — the print-industry default. For rotated pages the position is computed against the visual orientation, not the file’s storage axis.

Do page numbers work on rotated pages?

Yes. Some scanner apps write landscape pages as physically portrait pages with /Rotate 90 baked in. The tool detects this and places the number on the visual edge (top/bottom × left/center/right), not on the storage axis. Mixed-rotation documents get the correct position per page.

What happens to the PDF’s metadata?

The Producer, Creator and Author entries in the PDF Info dictionary are cleared on save by default — nobody reading the saved document can tell which software you used. Embedded fonts, rotations and the content stream of every page stay untouched.

Which related document tools fit this workflow?

Other tools in the kittokit ecosystem that fit this workflow:

• Merge PDF — combine multiple PDFs into a single document losslessly, locally in your browser.
• Split PDF — extract page ranges or individual pages from a PDF without uploading.
• Rotate PDF — flip individual pages or the whole document in your browser, with auto-detect for landscape scans.
• Reorder PDF pages — drag-and-drop the order, drop individual pages, all in the browser.