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OCR PDF

Make a scanned PDF searchable by adding a recognized text layer over the pages.

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Encrypted upload, deleted right after processingFree · No sign-up · No watermarks

Simple, practical guidance

How to use OCR PDF

Add a recognized text layer to a scanned PDF so its text can be selected and searched. Follow these steps to get a result you can confidently review, save, and share.

  1. 1

    Upload a scanned PDF.

  2. 2

    Choose the document language.

  3. 3

    Start OCR and wait for the text layer to be added.

  4. 4

    Download the searchable PDF and try selecting its text.

Get a better result

Clean scans at 300 DPI or higher recognize most accurately; pages that already contain text are left untouched.

Know how your file is handled

The file is sent to the configured processing server because this job needs software that a browser cannot provide. Avoid uploading documents you are not permitted to process.

Check before you share

Very low-resolution scans, handwriting, and unusual fonts reduce recognition accuracy.

Questions people ask

OCR PDF FAQ

Clear answers about file quality, privacy, compatibility, and what to expect from the conversion.

What does OCR PDF do?

Add a recognized text layer to a scanned PDF so its text can be selected and searched. It accepts a scanned or image-only PDF and produces a searchable PDF.

How do I use OCR PDF?

The process is straightforward. Upload a scanned PDF. Choose the document language. Start OCR and wait for the text layer to be added. Download the searchable PDF and try selecting its text.

Is OCR PDF available now?

OCR PDF is available now on Big PDF Tools.

Will OCR PDF reduce the quality of my document?

Clean scans at 300 DPI or higher recognize most accurately; pages that already contain text are left untouched.

Is it safe to use OCR PDF with private files?

The file is sent to the configured processing server because this job needs software that a browser cannot provide. Avoid uploading documents you are not permitted to process.

Can I use OCR PDF on a phone or tablet?

Yes. OCR PDF works in a modern mobile browser: the file is sent to the server for processing, so keep a stable connection and leave the tab open until the job completes.

Is there a maximum file size for OCR PDF?

The practical limit depends on the upload size and the processing server. If a very large file stalls, try a smaller file or split the work into manageable parts.

Does OCR PDF change my original file?

No — your original file stays unchanged. OCR PDF saves a searchable PDF as a separate download.

How long does OCR PDF take?

Small files usually finish quickly. Large page counts, high-resolution images, complex layouts, upload speed, and server load can all increase how long OCR PDF takes.

Why did my OCR PDF job fail or look different?

Very low-resolution scans, handwriting, and unusual fonts reduce recognition accuracy. Also confirm that the source file is not damaged, uses a supported format, and is not blocked by an unknown password.