Use the free PDF OCR Text Extractor below: your PDF never leaves your browser — all work happens on your device, and nothing is uploaded to any server.
When a PDF has no text
Some PDFs look like documents but behave like photographs. You can see the words, but you cannot select them, copy them, or search them. That is a scanned PDF: each page is an image, not text. It happens with old books, paper forms, receipts, and anything that went through a scanner. The words are trapped in pictures, and every normal text tool fails on them.
OCR — optical character recognition — is the way out. It looks at the picture of a page and reads the letters, turning the image back into real text. This tool does that entirely in your browser, using Tesseract.js, a well-known open OCR engine that runs locally as WebAssembly. No file is uploaded, and no account is needed.
How it works here
Upload a scanned PDF, pick the language, and choose how many pages to read. The tool renders each page as an image with pdf.js, then hands that image to Tesseract, which reads it and returns the text. You see progress page by page, and at the end you get the full text in a box you can copy, plus a download button for a plain text file.
Language choice matters. Pick English for English documents, Spanish for Spanish ones, or both when a document mixes the two. The wrong language makes OCR misread accented letters and common words, so a ten-second choice here saves a lot of fixing later.
Why it is slow, honestly
OCR is heavy work. Reading a page means analysing thousands of pixels and deciding, letter by letter, what each shape is. That is why the tool defaults to five pages and caps at thirty per run. A five-page letter finishes in well under a minute on a normal computer. A thirty-page chapter takes several minutes. A whole book should be done in batches, not in one heroic run.
Your device matters too. A recent desktop or laptop handles OCR smoothly. An old phone will struggle, and a very long run may heat the device or slow the browser. Work in small batches, keep the tab in focus, and let each batch finish before starting the next.
Getting accurate results
OCR accuracy lives or dies on scan quality. A clean, straight, high-contrast scan reads almost perfectly. A skewed, faint, or low-resolution scan will misread letters, drop punctuation, and merge words. If your results look messy, the scan is usually the problem, not the tool. Re-scan at higher resolution if you can, and make sure the page is straight.
Always proofread OCR output before relying on it. Numbers are the danger zone: a misread digit in a price, date, or measurement changes the meaning completely. Read numbers twice, and check names and technical terms against the original image. OCR gives you editable text; it does not guarantee perfect text.
What to do with the text
Once you have the text, the document opens up. You can search it, copy quotes from it, paste it into notes, translate it, or feed it into other tools — a reading time calculator, a Markdown converter, or a search tool. A scanned archive becomes a searchable archive, which is the real prize. Old family letters, out-of-print books, and paper records stop being pictures and start being usable text.
Keep the original scan alongside the text. OCR output is a working copy. If a passage is ever disputed, the image is the evidence.
Common questions
Does it work on handwriting? Poorly. Tesseract is built for printed text. Neat handwriting may partly read, but expect many errors.
Why is my PDF fast but empty? If the PDF already has a text layer, you do not need OCR at all — use a normal text extractor, which is instant.
Can I OCR a whole book at once? The tool caps at thirty pages per run. Do it in batches and join the text files afterwards.
Is my scan private? Yes. Rendering and OCR happen locally in your browser, and nothing is uploaded.
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