OCR PDF — make a scan searchable

Why OCR your PDFs with ModySign?

A scanned PDF is a frozen image: you can't search inside, select or copy text. Useless for searching across an archive folder, a scanned course, a faxed contract. OCR (Optical Character Recognition) fixes this by adding a text layer over the image — the PDF keeps its original look but becomes searchable.

Most online OCRs (Smallpdf, iLovePDF, OCR.space, Adobe Online) upload your documents to foreign servers. Unacceptable for medical, legal, HR or admin files. ModySign runs OCR entirely in your browser using Tesseract.js — your documents NEVER leave your machine.

Our OCR supports French, English and Spanish. The first run downloads the engine (~5-10 MB) and the chosen language model (~2-4 MB), cached in your browser afterwards: subsequent runs are instant. The final PDF looks exactly like the original but carries an invisible text layer — you can search with Ctrl+F, select and copy.

Questions fréquentes

Why is the first load so slow?+

The first run downloads the Tesseract.js engine (~5-10 MB of WebAssembly) and the chosen language model (~2-4 MB). These resources are cached in your browser — your next OCR runs are near-instant. Plan for 10 to 30 seconds the very first time depending on your connection, then almost nothing afterwards.

Is my PDF sent to your servers?+

No, never. Tesseract.js runs entirely in your browser via WebAssembly. Your PDF NEVER leaves your machine — unlike Smallpdf, iLovePDF, OCR.space or Adobe Online which upload your documents to process them on foreign servers.

Which languages are supported?+

For now: French, English and Spanish. Pick the document's main language before starting — it dramatically improves accuracy on accented characters (é, à, ñ) and language-specific vocabulary.

What OCR quality can I expect?+

On a clean scan (good resolution, light background, standard printed font), accuracy exceeds 95% — more than enough for keyword search. On blurry, skewed or handwritten scans, expect errors. Tesseract is a strong open-source OCR but stays below proprietary engines like Adobe ABBYY.

Does the generated PDF keep its look?+

Yes. Each page is re-embedded as a JPEG image with the recognised text layered on top at opacity 0 (invisible). Visually, the PDF is identical to the original scan, but you can now search with Ctrl+F and copy the text.