How do I make a scanned PDF searchable?
Upload your scanned PDF, select the document's language, choose which pages to OCR (all or specific ranges), pick output format and compression level, then click 'Start OCR'. Download the searchable PDF when processing completes. The document looks the same but now supports text search and copy-paste.
What languages are supported for OCR?
12 major languages are supported: English, Chinese (Simplified), Chinese (Traditional), Japanese, Korean, Spanish, French, German, Italian, Portuguese, Russian, and Arabic. Select the language that matches your document's text for best OCR accuracy.
Can I OCR only certain pages instead of the entire PDF?
Yes! Choose 'Custom ranges' and enter the pages you want, like '1-10' for pages 1 through 10, '5, 8, 12' for specific pages, or '1-5, 20-25' for multiple ranges. This saves time and creates smaller output files when you only need to OCR specific sections.
What's the difference between PDF, PDF/A-2, and PDF/A-3 output formats?
Standard 'PDF' is for everyday use with maximum compatibility. 'PDF/A-2' and 'PDF/A-3' are archival formats designed for long-term preservation and legal compliance - they embed all fonts, metadata, and ensure the PDF looks identical decades from now. Use PDF/A for official records, legal documents, and government archives.
How do compression levels affect the output?
Compression controls file size vs quality trade-off. None (no compression) = largest file, perfect quality. Low = slight reduction, near-perfect quality. Medium = balanced (recommended for most cases). High = smallest file, slight quality loss. Higher compression can make images slightly blurrier but significantly reduces file size.
What happens if my PDF already contains text?
The tool automatically detects existing text and shows text handling options: 'Skip text' (default) - OCR only image pages, keep existing text. 'Redo OCR' - Replace existing text with fresh OCR (useful if original text is inaccurate). 'Force OCR' - OCR all pages including text pages. This smart detection prevents redundant OCR on already-searchable pages.
Will the scanned PDF look different after OCR?
No. OCR adds an invisible text layer behind the images - the visual appearance, scan quality, colors, and layout remain exactly the same. You see the original scan, but search engines and text selection see the OCR text. This preserves authenticity while adding functionality.
How accurate is the OCR text recognition?
OCR accuracy depends on scan quality. High-quality, clear scans with good contrast yield 95-99% accuracy. Low-resolution, blurry, or damaged scans may have lower accuracy. For best results, use scans with at least 300 DPI resolution and clean backgrounds. Consider using our PDF Enhancement tool first to improve low-quality scans.
Can I OCR handwritten documents or cursive text?
OCR works best on printed text (books, typed documents, forms). Handwriting and cursive have lower accuracy and may produce garbled results, especially for messy handwriting. Clear, block-letter handwriting may work partially, but results vary.
What if my scanned PDF is tilted or has poor quality?
Use our 'Scanned PDF Enhancement' tool first to straighten tilted pages (deskew), remove backgrounds, and clean up artifacts. Enhanced scans produce much better OCR accuracy. Then use this OCR tool to add the text layer.
Can I make accessibility-compliant PDFs for screen readers?
Yes! Screen readers require text to read aloud to visually impaired users. Adding OCR text layer makes scanned PDFs accessible to screen readers like JAWS and NVDA, ensuring compliance with accessibility standards (WCAG, Section 508).
What happens to my PDF during OCR processing?
Small files (10MB or less) process on our server but are never stored - they convert and return immediately. Large files (over 10MB) are temporarily stored during processing and automatically deleted after 2 hours for privacy.
Is there a file size limit?
Yes, PDFs up to 200MB are supported. This accommodates lengthy scanned books, multi-page contracts, and large document archives.