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Recognize Text via OCR

Extract text from scanned PDFs and images using optical character recognition.

Text recognition runs on our server, which is what makes it accurate. Your file is never written to disk - it is read in memory and dropped the moment the job finishes.
Drop PDF or image file here or click to browse
Select a PDF or image file (JPG, PNG, etc.) to extract text

What OCR PDF Means

A scanned page inside a PDF is a picture. The file stores pixels, not characters, so searching, selecting or copying returns nothing. That is the gap OCR closes.

Optical character recognition analyses the shapes on the page, matches them against trained character models and returns real text. Running OCR on a PDF turns a flat scan into something you can search, quote and reuse. It is also how you extract text from a scanned PDF that was never typed digitally in the first place.

How PDF Text Recognition Works

After upload, each selected page is rendered as an image at recognition resolution. The engine (Tesseract) separates the page into blocks, lines and individual word shapes, then compares each glyph against the character set of the language you picked.

The result is plain text you can view, copy or download. When a searchable PDF is produced, that recognised text is placed as an invisible layer positioned over the original page image, so the scan looks unchanged while search and text selection start working. Files are processed on the server and are not kept afterwards.

How To Run OCR On A PDF Or Image

  1. Open the "Recognize Text via OCR" tool page.
  2. Upload a PDF file or an image (JPG, PNG, GIF or WebP).
  3. Choose the document language from the dropdown. English is selected by default.
  4. Optionally type the pages to process, for example "1, 3, 5-7". Leave the field blank to cover every page.
  5. Click "Recognize Text" and watch the progress bar for status.
  6. Review the extracted text, then use "Download as Text File" or "Copy to Clipboard".
  7. Click "Remove" to clear the result before starting another file.

File Types And Languages The OCR PDF Tool Accepts

Recognition runs on scanned documents and on ordinary photos or screenshots, which makes it a practical image to text step as well.

If your source is a set of photos, combine them first with JPG to PDF and recognise the whole document in one pass.

Getting Accurate Results From Scanned Text Recognition

Accuracy depends on the input image and the language model, not on the length of the document. Clean, straight scans at roughly 300 DPI give the strongest results.

Problem in the output Likely cause What to do
Letters replaced by random symbols Wrong language selected Re-run with the actual document language, including for accented or non Latin scripts
Words merged or broken apart Low resolution or heavy compression Rescan at 300 DPI, or use the original file instead of a compressed copy
Whole lines missing Skewed, curved or shadowed page Straighten the page and rescan flat with even lighting
Nothing recognised at all Handwriting or decorative script Printed type is required; handwriting is outside what the engine models
Columns mixed into one paragraph Complex multi column layout Process the page, then reorder the text manually after copying

When To Choose Text Recognition Over A Direct Converter

If a PDF was generated from a word processor, the characters already exist in the file and a converter can read them directly. Recognition is the right choice in different situations.

FAQ

OCR stands for optical character recognition. In a PDF it means reading the page as an image, detecting the shape of each printed character and converting those shapes into actual text data. A scanned PDF stores only pixels, so nothing is searchable until recognition runs. Afterwards you have text you can copy, download or place back over the scan as an invisible layer.

Upload the scan, pick the document language and run recognition. The engine maps every recognised word back to its position on the page, and a searchable PDF keeps the original page image with that text written invisibly underneath. Visually the document looks identical, but search, text selection and indexing now work because real characters exist in the file.

PDF files and single images in JPG, PNG, GIF or WebP format. PDFs are rendered page by page before recognition, while images are fed straight to the engine, which is why an image to text job usually finishes quicker than a long scanned report. Photos of printed pages work as long as the text is in focus and the page is not strongly tilted.

Each language uses its own trained character set and dictionary. That data decides how ambiguous shapes are resolved, for example separating an accented character from a plain one, or distinguishing similar Cyrillic and Latin letters. Choosing the wrong language forces the engine to guess with the wrong reference, which produces garbled words. Nineteen languages are available, including Japanese, Korean, Chinese, Arabic, Hindi and Thai.

Yes. Enter page numbers and ranges such as "1, 3, 5-7" and only those pages are rendered and recognised, which cuts processing time on long documents. Leaving the field empty covers the whole file. If you would rather work with a smaller document from the start, split it first with Extract Pages .

A converter reads character data that already exists inside the PDF and rebuilds it as paragraphs, fonts and tables in a DOCX file. Recognition creates that character data from scratch by interpreting pixels, because a scan contains none. So on a scanned file PDF to Word alone may return empty pages or images, while text recognition returns the wording without the original formatting.

The downloadable output is plain text, so fonts, colours and table borders are not reproduced. Reading order follows the blocks the engine detected, which works well for single column pages and can interleave text on complex multi column layouts. If you need the visual layout preserved, use the searchable PDF output instead, since it leaves the page image untouched.

Almost always the language is wrong or the scan quality is too low. Recognition depends on clean edges between ink and background, so blurry photos, heavy JPEG compression, shadows and skewed pages break character shapes apart. Rescan at around 300 DPI, keep the page flat and evenly lit, confirm the language, then run the file again.

No. The character models are trained on printed type, where letters have consistent shapes and spacing. Handwriting varies per writer and joins letters together, so the segmentation step cannot isolate reliable glyphs. Handwritten notes, signatures and decorative script fonts will either be skipped or returned as nonsense, while printed forms with handwritten entries still yield the printed parts.

Recognition needs real computing power, so the document is uploaded and processed on the server rather than in your browser. The file is used for that job only and is not stored permanently. You can also clear the result yourself with the "Remove" button once you have downloaded the text file or copied it to the clipboard.

No. The uploaded document is read, not rewritten, and the recognised text is delivered separately as a .txt download or clipboard copy. If a searchable PDF is generated, it is a new file in which the page images are identical and only an invisible text layer has been added. Your local copy on disk stays exactly as it was.