Why scanned PDFs need OCR
A scanned PDF is fundamentally different from a regular PDF. When you scan a document or photograph a page, the result is an image — a picture of text, not the text itself. From the software's perspective, there is no text in the file, only pixels arranged in patterns that look like letters. That is why you cannot highlight, copy, or search text in a scanned PDF.
OCR (Optical Character Recognition) solves this by analysing each page image, identifying individual characters, and reconstructing them as real, editable text. Once the OCR step is complete, the text can be placed into a Word document that you can edit, search, copy from, and reformat.
How to convert a scanned PDF to Word
- Open Filero's PDF to Word converter.
- Upload your scanned PDF. You do not need to do anything special — Filero automatically detects that the pages contain images rather than text and switches to OCR mode.
- Click Convert and wait. Scanned PDFs take slightly longer than regular PDFs (typically 30 to 60 seconds depending on the number of pages).
- Download your Word file and open it in Microsoft Word, Google Docs, or LibreOffice.
Getting the best OCR accuracy
The quality of the scan directly affects how accurately the text is extracted. Here is what makes a difference:
- Scan at 300 DPI for the best results. Most office scanners and phone scanning apps support this setting.
- Use black and white mode rather than colour for text documents. This increases contrast and improves character recognition.
- Keep pages straight. Heavily skewed or rotated pages reduce accuracy. If your scan is rotated, use Rotate PDF first.
- Avoid shadows and glare when photographing documents with your phone.
- Standard fonts work best. Handwriting, decorative fonts, and very small text (below 10pt) are harder for OCR to read.
Common use cases
- Old contracts and agreements that only exist as paper copies or scanned files and need to be updated
- Archived documents that were scanned years ago and now need to be edited or quoted from
- Signed forms that need to be converted back to editable format for record keeping
- Receipts and invoices scanned for expense tracking that need data extracted
- Academic papers or book chapters that were scanned from a physical copy
After conversion: cleaning up the Word file
OCR is highly accurate for clean scans but not perfect. After downloading your Word file, run a quick spell-check to catch any characters the OCR may have misread. Common OCR errors include confusing 'l' (lowercase L) with '1' (one), 'O' with '0' (zero), and missing spaces between words. For a clean 300 DPI scan, you may not need to fix anything at all.
Frequently asked questions
How does OCR work on scanned PDFs?
OCR (Optical Character Recognition) analyses the image of each page, identifies letter shapes and patterns, and converts them into real, editable text. Filero automatically detects when a PDF is scanned and switches to OCR mode without you needing to do anything different.
How accurate is the OCR?
For clean, high-contrast scans at 150 DPI or above, accuracy is typically 98 to 99 percent. Low-resolution scans, handwriting, decorative fonts, and heavily skewed pages produce less reliable results. Scanning at 300 DPI in black and white gives the best outcome.
Can I convert a photo of a document?
If the photo is saved as a PDF (many phone scanning apps export to PDF), yes. The OCR process works the same way on photographed documents. For best results, make sure the photo is well-lit, straight, and the text is clearly legible.
Is my scanned document kept private?
Yes. Your file is uploaded over HTTPS, processed with OCR, and deleted immediately after you download the Word file. Scanned documents often contain sensitive information, so nothing is stored or shared.