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OCR PDF

A scanned PDF is just pictures. OCR recognizes the words and writes them as an invisible layer under the image, so the document becomes searchable and the text can be copied — while it still looks exactly like the scan.

By Miikka · CalcBrew · Updated

Runs in your browser when it can; large or unusual files use our EU server and are deleted within 1 hour.

Drop PDF, JPG, PNG, TIFF file here

or click to browse · paste from clipboard · up to 300 MB

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Why convert PDF to PDF

Archives of scanned contracts, receipts and books are useless to search until they are OCR’d. Once processed, Spotlight, Windows Search and Acrobat find text inside them, and you can copy quotes instead of retyping.

Up to about 20 pages, recognition runs entirely in your browser with Tesseract compiled to WebAssembly. Larger files are sent to our server, where the same engine runs much faster; either way the output is the original image plus a text layer, so nothing visible changes.

How to convert files to PDF

  1. Drop your files onto the box above, click it to browse, or paste from the clipboard.
  2. Adjust the options if you need to — the defaults suit most cases.
  3. Press Convert. Small files are handled on your device; larger ones are sent to our server with a progress bar.
  4. Download the PDF.

About the formats

PDF · Portable Document Format · .pdf

The fixed-layout document standard: looks the same on every device and printer, which is why forms, invoices, contracts and reports are shared as PDF.

  • A PDF can contain vector text, embedded fonts, images, form fields, annotations and digital signatures.
  • Scanned PDFs are just pictures of pages; they need OCR before the text can be searched or copied.
  • PDF is an open ISO standard (ISO 32000) since 2008.

JPG · JPEG image · .jpg

The universal photo format: small files, supported by every device, camera and website, but no transparency and slight quality loss on each save.

  • JPEG compression discards fine detail the eye rarely notices; quality 80–90 is usually indistinguishable from the original at a fraction of the size.
  • Re-saving a JPG repeatedly adds generation loss, so keep an original and export copies.
  • JPG has no alpha channel — transparent areas become white or black when converted from PNG.

PNG · Portable Network Graphics · .png

Lossless image format with transparency, ideal for screenshots, logos, icons and graphics with sharp edges or text.

  • PNG is lossless: every pixel is preserved, which is why photos saved as PNG are 5–10× larger than JPG.
  • Supports an 8-bit alpha channel, so edges can be partially transparent.
  • Most browsers and apps have supported PNG since the late 1990s.

TIFF · Tagged Image File Format · .tif

The archival and print standard: lossless, supports layers, multiple pages and 16-bit color, but far too large for the web.

  • TIFF can be uncompressed or losslessly compressed (LZW, ZIP); either way files are large.
  • Scanners and fax software often produce multi-page TIFFs.
  • Browsers do not display TIFF, so it must be converted to JPG or PNG for the web.

Related conversions

PDF to TextOn-deviceAll the text in a PDF as a plain .txt file.PDF to WordPopularEditable DOCX from a PDF’s text, with headings and paragraphs rebuilt.Scan to PDFOn-deviceCamera scanner: photograph pages, get a clean PDF.JPG to PDFPopularOn-deviceCombine JPG photos into a PDF document.PNG to PDFOn-deviceTurn PNG screenshots and graphics into a PDF.Image to PDFPopularOn-deviceAny image formats, mixed, into one PDF.

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Frequently asked questions

Cite this calculator
APACalcBrew. (2026). OCR PDF. https://calcbrew.com/ocr-pdf
MLA“OCR PDF.” CalcBrew, 2026, calcbrew.com/ocr-pdf.

Link to https://calcbrew.com/ocr-pdf. Results are estimates; cite the underlying formula or data source for academic work.