How to OCR a Scanned PDF (Make It Searchable)

An image-only scanned PDF can't be searched, copied, or read by screen readers. OCR fixes all of that — and most online tools do it automatically.

Key takeaways

  • Convert to Word for editable text + automatic OCR
  • Acrobat Pro for searchable-image PDFs that look identical to the original
  • 300 DPI greyscale scans give the best OCR accuracy

Two paths

Path 1: convert to Word (PDF to Word) — OCR runs automatically and you get an editable DOCX. Path 2: produce a 'searchable image' PDF that keeps the original look but adds an invisible OCR text layer underneath. Path 2 needs Acrobat Pro or PDF24 desktop.

Step-by-step (Path 1)

Upload your scanned PDF to our PDF to Word converter. OCR runs in seconds, layout analysis reconstructs paragraphs and tables, and you download a fully editable DOCX.

Step-by-step (Path 2)

In Adobe Acrobat Pro: Tools → Scan & OCR → Recognize Text → In This File. Acrobat detects all image-only pages and adds a hidden text layer. The PDF looks identical but is now searchable, copyable, and accessible.

Improving accuracy

Higher-resolution scans = higher OCR accuracy. Re-scan at 300 DPI greyscale if your originals are blurry or low-resolution. See our OCR guide for the full breakdown.

Frequently asked questions

Is OCR free?

Yes — our converters run OCR automatically at no cost. Tesseract (open source) and PDF24 desktop also offer free OCR.

How long does OCR take?

On a typical scanned PDF (10–20 pages), under 30 seconds. Larger scans scale linearly.

Will OCR change how the PDF looks?

In a 'searchable image' PDF, no — the original page image stays on top and the text is added as an invisible layer underneath.