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PDF OCR

Make scanned PDFs searchable while preserving the original page appearance: OCR adds an invisible selectable text layer over each rendered page and also provides a plain-text companion file.

The original scanned-page visual is preserved in the searchable PDF. OCR accuracy depends on scan quality, contrast, font clarity and the selected language; always review critical text after conversion.

Drag & drop files here

or use the button below · processed locally on your device

Output settings

Free file tool

Free PDF OCR online

Make scanned PDFs searchable while preserving the original page appearance: OCR adds an invisible selectable text layer over each rendered page and also provides a plain-text companion file. Use the tool directly in your browser with no sign-up. It supports multiple source files in the same session, so it also works as a free batch tool when you have more than one file.

Free to use

No payment required for this tool.

Batch conversion

Queue multiple source files in one session.

Browser-based

The conversion workflow runs from the web page on your device.

No sign-up

Start the file workflow without creating an account.

What PDF OCR is useful for

  • Reusing information stored in a PDF
  • Moving document content into an editable format
  • Extracting text or structured content for review

Input and output checks

Accepted input: Text or settings entered on the page.

  • Open the downloaded output before deleting or replacing the source file.
  • Check the details that matter for your use: page count, dimensions, orientation, text, duration or metadata.
  • For batch jobs, confirm every queued file produced the expected output.
  • If quality or size matters, compare more than one settings combination before choosing the final copy.

How to use this calculator: PDF OCR

  1. 1Upload a scanned or image-based PDF and choose the OCR language and render scale.
  2. 2Each PDF page is rendered locally in your browser and analysed with OCR.
  3. 3The original page visual is preserved while an invisible searchable text layer is added over the page.
  4. 4The tool verifies that the searchable PDF keeps the same page count as the source document.
  5. 5Download the searchable PDF and the companion TXT file, then review important recognised text before reuse.

Worked conversion example

Example: upload a clear, upright scan with good contrast. Review every extracted character—blur, handwriting, skew and decorative fonts reduce OCR confidence.

Accepted input
Text or settings entered on the page
Batch behaviour
Multiple files supported

Output settings

SettingExample/defaultEffect
LanguageEnglishChanges how the output is encoded or arranged; preview the result before relying on it.
Render scale2Changes how the output is encoded or arranged; preview the result before relying on it.

How the browser process works

Make scanned PDFs searchable while preserving the original page appearance: OCR adds an invisible selectable text layer over each rendered page and also provides a plain-text companion file. The page sends the selected file and settings to its ocr-pdf browser engine, creates a new output and downloads it without overwriting the source.

The original scanned-page visual is preserved in the searchable PDF. OCR accuracy depends on scan quality, contrast, font clarity and the selected language; always review critical text after conversion.

Privacy, quality checks and limitations

  • Keep the original file until the downloaded output has been opened and checked.
  • Verify page count, orientation, dimensions, text legibility, audio/video duration and metadata relevant to your use.
  • Browser-local processing reduces routine upload exposure, but your device, browser extensions and download location still matter.
  • A converted preview is not proof of legal authenticity, archival compliance, accessibility or digital-signature validity.

Run OCR on scanned PDF pages to recognise text and make image-based documents more useful for search and extraction. Choose an OCR language and render scale in the existing tool.

What is PDF OCR?

OCR stands for optical character recognition. It analyses an image of a document and attempts to recognise characters and words that are not available as normal selectable PDF text.

When should you use OCR?

  • The PDF is a scan of printed pages.
  • You cannot select text in the PDF.
  • You need to search or extract text from a scanned document.
  • You need a text-recognition step before another document conversion.

OCR accuracy

OCR results depend on scan resolution, lighting, contrast, fonts, language, page layout, and image quality. Always review important extracted text before relying on it.

Frequently asked questions

Does PDF OCR change the visual appearance of my scanned pages?

The searchable PDF keeps the original scanned-page visual and adds a transparent recognised-text layer for searching and selection.

Does PDF OCR make the text searchable?

Yes. The generated PDF includes an invisible OCR text layer so recognised words can be searched and selected while the page image remains visible.

Will PDF OCR always recognise every word correctly?

No. OCR accuracy depends on scan resolution, contrast, skew, font clarity, language and page complexity. Review important names, numbers and technical values after conversion.

Does the tool also provide extracted plain text?

Yes. The OCR workflow also generates a TXT companion file containing the recognised text page by page.

Are my scanned PDFs uploaded to a server?

The OCR workflow runs in the existing browser-side processing path, so supported OCR work is performed locally on your device.

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