OCR PDF

Extract searchable text from scanned documents.

Guide & FAQ

About this tool

Turn scanned PDFs and image-only documents into searchable, copy-friendly files - recognise text inside your browser with Tesseract.js, without uploading pages to a cloud OCR farm. Pick languages, run recognition locally, and download a PDF with a hidden text layer aligned to the visible scan. Free, no account. Essential for archival contracts, government forms, and research PDFs where you need Ctrl+F, copy-paste, or a later PDF-to-Word pass.

What you get
  • Output: PDF with an invisible text layer over each page - search and copy work in Acrobat, Preview, and browsers.
  • Engine: Tesseract LSTM running locally via WebAssembly - no third-party OCR API by default.
  • Languages: multi-language packs combined with + - accuracy depends on training data for each script.
  • Visuals: page appearance stays the scan; OCR does not retypeset or clean skewed margins automatically.
  • Handwriting: cursive and signatures usually fail or partial - typed print works best.
  • Limits: large scans at 300 dpi take time on older laptops; very faint text or heavy noise reduces accuracy.
When to use
  • Making a legacy paper archive searchable without sending volumes to an external OCR vendor.
  • Preparing scanned contracts for PDF to Word when born-digital text isn't available.
  • Enabling copy-paste from government PDFs that are technically images.
  • Indexing meeting packets scanned from printouts for internal knowledge bases.
Why JoyPDF for this

Cloud OCR services upload every page - including signatures, account numbers, and classified paragraphs - to recognise text remotely. JoyPDF OCR runs entirely in your browser: pixels and recognised strings stay on-device during processing. You pick languages explicitly instead of a server guessing. That fits GDPR, legal privilege, and air-gapped-adjacent workflows where outbound document transfer is prohibited.

How to use
  1. 1Add your scanned PDFDrop the file or select it from your device. Pages load locally - no server-side OCR queue.
  2. 2Choose OCR languagesSelect recognition languages - e.g. English, Polish, or combined eng+pol for bilingual scans.
  3. 3Run recognitionJoyPDF processes each page on your device; progress shows per page because OCR is CPU-intensive.
  4. 4Download searchable PDFSave the OCR'd file - visually similar to the scan but with selectable, searchable text underneath.

Common questions

Which languages does JoyPDF OCR support?
JoyPDF uses Tesseract language packs you select - common Latin scripts (English, Polish, German, French, Spanish, etc.) and many others depending on available traineddata. Combine languages with + for bilingual documents, e.g. pol+eng for Polish body text with English headings. Wrong language choice produces gibberish recognition - match the document, not your UI locale. Rare scripts or mixed vertical text may need specialist desktop OCR if JoyPDF results are poor. Downloaded language data loads into the browser session; it is not sent back with your PDF.
How accurate is browser OCR compared to Adobe?
Clean office scans at 200-300 dpi with horizontal typed text often reach high accuracy - good enough for search and rough copy-paste. Skewed phone photos, stamps over text, tables with rules, and footnotes reduce precision in any engine. JoyPDF won't beat a human retyping a critical clause - always spot-check legal and medical strings. Adobe's cloud OCR may edge ahead on tough layouts but requires upload. For internal searchability on bulk archives, local OCR trade-offs usually win on privacy.
Does OCR change the visual appearance of my PDF?
The scan image remains the visible layer - OCR adds an invisible text layer beneath for search and selection. You shouldn't see font swaps on the page itself unless your viewer highlights OCR text. File size may grow modestly from embedded text streams. If you need a clean retyped document, OCR then PDF to Word works better than expecting OCR alone to replace the scan visually. Redacting after OCR requires Redact PDF - OCR doesn't remove sensitive pixels.
Is my scanned PDF uploaded during OCR?
No. Recognition runs locally with Tesseract.js in WebAssembly. Page images are processed in memory on your device; JoyPDF servers don't receive document bytes for OCR. Language model files download from CDN like any WASM dependency - not your document content. Verify with network tools if compliance requires proof. Close the tab after export on shared machines because OCR output may contain extracted PII in the text layer.
Can I OCR a PDF then convert it to Word?
Yes - that's a common pipeline. Scanned PDFs lack structure for PDF-to-Word until OCR adds text. Run OCR PDF first for searchable text, then PDF to Word for editable paragraphs - or enable OCR-first options in PDF to Word when offered. Double-OCR rarely helps. For forms with checkboxes, expect manual cleanup in Word regardless. If only search matters, OCR alone suffices without Word conversion.
Why is OCR slow on my computer?
OCR is CPU-heavy: each page is analysed at image resolution you embedded in the scan. A 300 dpi, 200-page book can take many minutes on an older laptop - normal, not a bug. Close other tabs to free RAM. Split the PDF and OCR chapters separately if the tab crashes. Progress callbacks show per-page status. Faster hardware helps more than retrying. Overnight batch on desktop beats fighting a phone browser for huge archives.

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