How to Convert Scanned PDFs and Images into Searchable, Copyable Text
The Problem with Scanned PDFs
When you scan a paper document using a physical scanner or smartphone app, the output PDF is often just a container holding flat image pixels.
Even though you can see words on your screen, your computer cannot recognize them as text. You cannot search for key terms (Ctrl+F), copy quotes into Word, or feed the document into screen readers or AI summarizers.
What is Optical Character Recognition (OCR)?
Optical Character Recognition (OCR) is a technology that analyzes image pixels, detects line patterns and character shapes, and translates them into machine-encoded text characters (ASCII and Unicode).
Historically, OCR required heavy desktop applications or expensive server APIs. Today, client-side WebAssembly models allow us to run neural-network OCR engines directly inside your web browser.
How Client-Side OCR Works in Your Browser
PDF Section uses Tesseract.js compiled to WebAssembly to provide instant, browser-native text recognition:
- Canvas Rasterization: The uploaded PDF page is rendered to an HTML5 canvas at high resolution.
- Binarization & Contrast Enhancement: Image pixels are pre-processed to convert colored artifacts into high-contrast black and white text shapes.
- Neural Character Extraction: The WebAssembly engine scans character contours, matching glyph patterns against trained language models.
- Text Output: Extracted text blocks are compiled into copyable text segments ready for editing or exporting.
Step-by-Step Guide to OCR Scanned Files
- Navigate to the OCR PDF page on PDF Section.
- Drag and drop your scanned PDF file or document image.
- Click Run OCR Page Scanning.
- Watch the real-time progress bar as character recognition processes page by page.
- Copy the extracted text output to your clipboard or download it as a text document.
No account registration is needed, and your scanned contracts or personal notes never touch an external server.