OCR PDF — Make Scanned PDFs Searchable

Turn scanned PDFs and photographed documents into searchable, copyable files — free, with no sign-up. Allypdf runs the open-source Tesseract OCR engine as WebAssembly inside your browser: each page is recognized locally and rebuilt with an invisible text layer over the original scan. No cloud OCR API is involved, so your document is never uploaded anywhere.

How to OCR a scanned PDF with Allypdf

  1. Load a scanned PDF or a photo of a document.
  2. Pick the document's language (English, Spanish, French, German, Italian, Portuguese, or Dutch).
  3. Click Run OCR — pages are recognized one at a time on your device, with live progress.
  4. Download the searchable PDF and copy or download the recognized plain text.

How local OCR keeps your scans private

The documents people OCR are scans — and scans are usually the papers that matter: signed contracts, ID documents, medical records, old tax paperwork. Every mainstream OCR service works by uploading those images to a cloud API that reads them on someone else's servers. Allypdf takes the opposite approach: the OCR engine itself is downloaded to your browser (once, a few megabytes) and your document is processed entirely on your own hardware. Nothing you scan is ever transmitted, logged, or retained.

Common uses

  • Make a scanned contract searchable so you can Ctrl+F clause names instead of re-reading every page.
  • Copy quotes out of a scanned book chapter or printed article for notes or citations.
  • Digitize a printed letter, receipt, or certificate into editable text without a scanner app account.
  • Turn photographed meeting handouts into a searchable PDF for your records.

Frequently asked questions

How do I make a scanned PDF searchable for free?

Load the scan into Allypdf's OCR tool, choose its language, and click Run OCR. The recognized words are added as an invisible text layer over your original pages, so the downloaded PDF looks identical but is fully searchable and copyable. Free, no watermark, no account.

Is my document sent to a cloud OCR service?

No. Allypdf uses the Tesseract engine compiled to WebAssembly, running inside your own browser. On first use it downloads the engine and language pack (a few megabytes) from a CDN — a one-way download. Your document itself never leaves your device, unlike Google Vision or AWS Textract-based tools.

How accurate is the recognition?

Very good on clean, straight, high-contrast scans of printed text; noticeably worse on skewed, blurry, low-resolution, or noisy pages. Handwriting is largely beyond it. Every result includes a confidence score, and the original scan is always preserved unchanged underneath the text layer.

Which languages can it recognize?

English, Spanish, French, German, Italian, Portuguese, and Dutch. Selecting the right language before running OCR makes a real difference to accuracy, because each language pack contains its own trained recognition model.

Why is OCR slower than other Allypdf tools?

Character recognition is genuinely heavy computation, and it runs on your hardware rather than a server farm — that's the privacy trade-off, stated honestly. Pages are processed one at a time with a live progress bar; a typical page takes a few seconds on a modern machine.

Can I OCR a password-protected PDF?

Not directly. Remove the password first with Allypdf's Unlock PDF tool (you need to know the password), then run OCR on the unlocked copy. Both steps happen entirely in your browser.

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