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My file is all scanned images; will page numbers still print on those pages?

Yes. The tool does not need any text on the page: it draws the number as new text on top of the page whatever the page contains, image or text. An 8-page scan gets numbered 1 to 8 like any other file. The one thing to watch is that scanned pages often have dark edges or shadows, so check the preview and choose a light spot for the number.

Published · 3 min read

Why people ask

Because a lot of PDF tools rely on the text inside the file, for searching or copying, and fail on scans because a scan is only pictures. Numbering is different: it reads nothing from the page and only adds on top. So it works on invoices photographed with a phone, contracts scanned at the office and receipts gathered into one file.

The steps with a scanned file

  1. If you have separate photos of the sheets, put them into one file in the right order with Images to PDF first.
  2. Open PDF page numbering and choose the file.
  3. Pick the format and position, then press Add numbers.
  4. Open the preview and move through several pages, not just the first, because each scanned page can differ from the one before.
  5. Download. The result line confirms how many pages were numbered and the first and last label.

Scan-specific problems and fixes

  • Black borders or a cover shadow: scanners and phones sometimes capture what lies around the sheet. If the number falls on a dark strip, raise the margin so it moves onto the white paper.
  • Slightly skewed pages: the number is placed square to the page boundary, not to the photographed sheet inside it. A small tilt goes unnoticed; a large one is better rescanned.
  • Grey or yellowed background: old paper shows up tinted. The default dark number usually stays readable, and you can change its colour if you need stronger contrast.
  • Mixed sizes: a small receipt next to an A4 page. The position is worked out per page from its own size, so a bottom centre number sits in the middle of each page whatever its width.

What does not happen

Numbering does not make scanned pages searchable and does not turn the image into text. The only real text added to the file is the number itself. Nor does the tool remove old numbers written on the original paper, so if the sheets carry handwritten or printed numbers, put the new number in a corner away from them.

Mind the size too: high-resolution scans are heavy, and the tool's tested limit is one file of up to 100 MB and 500 pages.

Common questions

Does the file get bigger after numbering?

Usually only a little, because the numbers are text with an embedded font, not new images. The scanned images themselves are not recompressed.

Does the quality of the scans change?

No. The tool does not redraw the images; it only adds the number on top of them.