Add OCR Text Layer to Scanned PDF
Upload a scanned or image-only PDF and get back a copy that looks exactly the same but is now searchable and has selectable, copyable text - OCR runs entirely in your browser.
Häufig gestellte Fragen
Will the PDF look different afterward?
No. Each page's original image is kept exactly as-is - the recognized text is drawn on top at matching positions but made fully invisible, so visually the file is unchanged. It just becomes searchable, selectable and copyable underneath.
How do I know the text layer actually works?
After processing, this tool re-extracts the text from the file it just built, using the same extraction the PDF to Text tool uses, and shows you how many searchable words it found. If that count is 0, something about the scan (very low quality, wrong language, or a genuinely blank page) likely prevented OCR from reading it.
How accurate is the recognized text?
It depends entirely on the scan quality - clean, high-resolution, well-lit scans of printed text recognize very well, while blurry, skewed, low-resolution or handwritten pages will have more mistakes. This tool makes documents searchable, it doesn't guarantee perfect recognition, so don't rely on the hidden text being 100% correct.
Which languages are supported?
Pick the document's language before processing - the OCR engine loads a language-specific model, so matching it to your document's actual language gives noticeably better results than leaving it on the wrong one.
Is my PDF uploaded anywhere?
No. Rendering, OCR and rebuilding the PDF all happen locally in your browser using pdf.js, Tesseract.js and pdf-lib - the file is never sent to a server.