What is OCR and why do scanned PDFs need it?
OCR (Optical Character Recognition) is the technology that converts an image of text into machine-readable characters. When you scan a document, the scanner creates an image of each page — like a photograph. Without OCR, the PDF contains no text data: you cannot search it, select text, copy from it, or use it in any text-processing workflow. Running OCR adds an invisible text layer that mirrors the visual text, making the document fully searchable, selectable, and accessible.
How to OCR a PDF free online — step by step
- Open ihatepdf.cv/ocr-pdf — no sign-up required
- Drop your scanned or image-only PDF onto the upload area
- Select the primary language of the document for best accuracy
- Click Recognize Text — Tesseract.js processes each page locally in your browser
- Copy the extracted text directly, or download as a .txt file — no watermark
How to tell if your PDF needs OCR
Open the PDF and try to select a word by clicking and dragging. If you can highlight individual words, the PDF already has a text layer — use Extract Text instead. If your cursor shows a crosshair and you can only draw a box over the whole page, it's an image-only PDF that needs OCR first.
What to do after OCR
- Search the document — press Ctrl+F / Cmd+F to search for any word
- Copy specific sections — select and copy text exactly as in any digital document
- Translate — paste extracted text into DeepL or Google Translate
- AI analysis — feed the text to Chat with PDF or AI Summarizer
- Edit — take the extracted text into a word processor and reformat
Tips for best OCR accuracy
- Scan at 300 DPI minimum — higher resolution significantly improves accuracy
- Black and white scan mode — higher contrast produces cleaner character recognition
- Straight scanning — skewed pages reduce accuracy; scan pages flat
- Select correct language — the right language model makes a major difference for non-English text
OCR in languages other than English
Recognition accuracy depends heavily on choosing the right language before you run it, because the engine uses a language-specific model to decide which characters it is seeing. Tesseract — the engine behind this tool — supports a wide range of languages including Spanish, French, German, Portuguese, Italian, Hindi, Arabic, Chinese, Japanese, and many more, as well as accented Latin scripts. Select the document's primary language from the list before clicking Recognize Text; for a page that mixes languages, pick the one that dominates and proofread the rest.
From a phone photo to a searchable PDF
You do not need a flatbed scanner to use OCR. Photograph the document with your phone, turn the images into a PDF with Scan to PDF or Images to PDF, then run that file through OCR here to add a real text layer. The result is a searchable, selectable PDF you can archive, full-text search with Ctrl+F, or feed into Chat with PDF — built entirely from a few phone snapshots.
Frequently asked questions
Can OCR read handwriting?
Only roughly. OCR is built for printed and typed text; neat handwriting may reach 40–70% accuracy, while cursive or messy writing is largely unreliable. For typed documents, expect 95–99% on a clean scan.
Which languages does the OCR support?
Many — including major European languages, Hindi, Arabic, Chinese, Japanese, and more. Select the document's main language before running OCR so the correct recognition model is used.
Is my file uploaded to a server?
No. OCR runs locally in your browser using Tesseract.js via WebAssembly. Your file never leaves your device.
How accurate is the text recognition?
Clean 300 DPI scans of typed text: 95–99%. Standard office scans (150–200 DPI): 85–95%. Handwritten text: 40–70% depending on clarity.
Does the output have a watermark?
No. ihatepdf never adds watermarks to any output.