How to scan documents to PDF

Phone camera or flatbed scanner

A flatbed scanner gives even light, straight pages and predictable resolution, so it is the better choice for books, old paper and anything you will keep. A phone is faster and good enough for one-off documents such as a signed form, a receipt or a page from a notebook.

Whichever you use, the goal is the same: a sharp, straight, evenly lit image where every character is clear. Everything after capture, including OCR, depends on that.

Capture pages that look professional

Most bad scans share the same causes: shadows, glare, skew and blur. A few habits remove almost all of them.

• Place the page flat on a plain, contrasting surface, such as a dark table under white paper.
• Use daylight or an even overhead lamp. Avoid your own shadow falling across the page and avoid flash, which creates glare on glossy paper.
• Hold the phone parallel to the page, directly above it, so the edges stay straight and text is not stretched.
• Fill the frame with the page while keeping all four edges visible, since the tool does not crop automatically.
• Tap to focus and hold still. Retake anything blurred, because sharpness cannot be added later.

Build the PDF with Scan to PDF

Scan to PDF runs in your browser, so the images never leave your device. On phones and tablets it adds a camera capture button, so you can photograph pages one after another; on a computer you can add scanner output or existing photos.

• Open Scan to PDF and take photos with the camera button, or add image files.
• Drag pages into the right order and rotate any that came in sideways.
• Choose the page size: fit to image, A4 or US Letter, and the orientation.
• Pick a margin (none, small or big). No margin suits full-page scans; a small margin looks tidier when printed.
• Create the PDF, which places one image per page, then download it.

Use the document filter wisely

The optional document filter has two modes: grayscale with a contrast boost, and black and white. It flattens uneven paper tones and makes text darker, which suits whiteboards, notes and plain printed pages.

Do not apply it to photographs, colour charts, stamps or anything where the colour carries meaning, such as a coloured signature. When unsure, keep the original colours; you can always shrink the file afterwards.

Keep the file size reasonable

JPG and PNG images are embedded without recompression, so a PDF built from full-resolution phone photos can be large. Ten photos of several MB each will produce a file that many email services refuse.

If the file is too big to send, run it through Compress PDF, which re-encodes the embedded images at a lower resolution while keeping the page layout. Compress after scanning and before OCR only if you have tested that the text is still readable at the lower quality.

Make the scan searchable

A scanned PDF is a set of pictures. To search it or copy text, run it through OCR PDF, which adds an invisible text layer in your browser. For the best results, capture at a good resolution and choose 300 DPI in the OCR settings for small print.

OCR recognizes printed text well and handwriting poorly, so a handwritten note will stay a picture for practical purposes. If you also need to crop away a table edge or margin afterwards, Crop PDF changes the visible area of the page without redoing the scan.

Privacy and good habits

Scans of identity documents, medical papers and contracts are sensitive. Because Scan to PDF processes images in your browser, they are not uploaded, but the original photos may also sit in your phone gallery or cloud backup, so delete them if you do not want copies around.

Name the file clearly, for example with the document type and date, and keep the original paper when it has legal value. A scan is a copy, and some procedures still ask for the original.