How to OCR a PDF Online — Free, 100+ Languages, No Watermark

A 500-page archive of scanned legal briefs is unsearchable — every search returns nothing because the file is just images. OCR adds an invisible text layer underneath the images, and suddenly Ctrl-F works and the search engine finds the documents.

When you actually need OCR PDF

Legal archives that need to be searchable, historical documents being digitised, customer support knowledge bases built from scanned manuals, research papers downloaded as image-PDFs from old databases.

How to ocr pdf, step by step

Open the tool

Go to convertpdfgo.com/ocr. No account, no email, no installation.

Drop the file in

Drag the file onto the upload area or click to pick. Files up to 30 MB go through without a queue. Encrypted in transit (TLS 1.3), encrypted at rest, deleted within one hour.

Configure

Pick a language (eng / rus / uzb / uzb_cyrl etc.). English is the default.

Download

Open in any reader, paste anywhere, feed to scripts.

Common problems and how to avoid them

OCR returned garbage characters

The scan is too low resolution or the original is a handwritten / unusual font. Try a higher-DPI scan, or use a script-specific language code (e.g. uzb_cyrl for Cyrillic Uzbek).

Output looks the same — no text layer visible

Open in Adobe Reader and try Ctrl-F. The text layer is invisible by design — it sits under the image.

Slow on large files

OCR is CPU-heavy. A 100-page scan takes 2-5 minutes. Smaller files run faster; consider splitting large archives.

A short word on privacy

Three things to know. One: files go over TLS 1.3. Two: files are encrypted at rest while we process them, then deleted automatically within one hour. Three: we don't look at your files or train on them.

How we compare to other free tools

Feature	convertpdfgo	Smallpdf	iLovePDF
Sign-up	None	After 2/day	Optional
Watermark	None	None	None
Auto-delete	1 hour	Vague	2 hours

Frequently asked questions

How accurate is the OCR?

Tesseract on clean scans hits 95-99% on Latin scripts; lower for handwriting, low-DPI scans, or unusual fonts. We use ocrmypdf as the wrapper — quality is what production tools ship.

Does it work on photos of paper?

Yes — convert the photo to PDF first (use JPG to PDF), then run OCR. Or use Scan to PDF which combines both steps.

Are my files private?

Files are encrypted in transit (TLS 1.3) and at rest, then auto-deleted within one hour.

Will it work on protected PDFs?

Not directly — unlock the PDF first with our Unlock PDF tool if you know the password.

Is there a usage limit?

No. Free, no daily cap, no sign-up wall, no watermark.

How long does it take?

About 5-30 seconds depending on file size and OCR complexity. Multi-page scans take longer.

What's the file size limit?

30 MB as a guest, 50 MB when signed in.

What to do next

Now you can Scan to PDF, Extract Text, or Compress PDF. All free.

Or browse our full list of 49 free PDF tools.