How to OCR a PDF

Publish date

Aug 22, 2026

AI summary

Use a browser tool to upload a scanned PDF (or image), run OCR, then download the searchable PDF; verify the result by searching and selecting text, ensure page count and file size fit your plan, and keep the original scan until the OCR output works correctly.

Language

You have a PDF on screen. The words look real. You hit Cmd-F (or Ctrl+F) for a name, and the finder returns nothing. You cannot select a sentence to paste.

You almost certainly have a scanned PDF. To make it searchable, you OCR it: the software reads the page image and writes a text layer back into the PDF.

This article is the how-to. For scanned vs digital files, and what a text layer actually is, start with OCR PDF: Make a Scanned File Searchable. You can run the steps below in a browser. You do not need a desktop app for a single file.

Before you OCR a PDF

Spend ten seconds on the file you already have:

Open it in any PDF viewer.

Try to drag-select a word in the body text.

Search for a word you can clearly see.

If the word highlights and the finder matches it, you already have a digital PDF. Stop. You do not need OCR for search.

If nothing highlights, continue.

Also check the file against the live PDF.ai pricing table before you upload:

File type. The OCR PDF tool accepts PDF, PNG, JPG, and WebP.

OCR page cap. Hobby 2 pages/file, Pro 10 pages/file, Ultimate 50 pages/file, Enterprise 100 pages/file.

Max file size. Hobby 10MB, Pro 50MB, Ultimate 50MB, Enterprise 100MB.

If the scan is longer than your plan’s page cap, split the file first, or use a plan that covers the page count. Do not assume a 200-page archive will go through on Hobby.

How to OCR a PDF

1. Open the OCR tool

Go to https://pdf.ai/tools/ocr-pdf. The page says it will OCR your PDF to make text searchable and selectable. The upload box is labeled Click to upload or drag and drop.

This is a browser tool, so the same steps work on Windows, Mac, and Linux. You do not install anything for this path.

2. Upload the file

Drop the scanned PDF, or a page image if that is what you have. Wait until processing finishes.

3. Download the result

Download the new file. Keep the original scan until you have checked the output.

That is the whole happy path: upload → OCR → download a searchable PDF.

Check the output before you trust it

Open the new file and repeat the same test:

Search for a distinctive word from the first page.

Search for a word from the last page you care about.

Select one sentence and paste it into a notes app.

If those three work, you have a searchable PDF. Archive that copy.

Practical rule: do not delete the original scan until search and selection work on the pages you need. OCR is a new file, not a guarantee.

If search still fails, check three things before you run the same file again:

You uploaded the scan, not a different PDF.

The page count and file size fit your plan.

The worst page is actually readable. If a person would squint, OCR will too. The longer failure list lives on the OCR PDF pillar.

Important distinction: a searchable PDF can still contain wrong characters. Search proving that some text exists is not the same as every number being correct.

OCR a PDF vs convert to Word

These two jobs get mixed up because both start with “I cannot edit this PDF.”

OCR a PDF when you want to keep the PDF and make it searchable. You gain find, select, and copy. The page still looks like the scan.

Convert to Word when you want an editable .docx you will rewrite. That is a conversion problem, not an OCR-PDF problem.

If the output you want is still a PDF you can search, stop at OCR.

A short action plan

Open the file and try select plus Cmd-F / Ctrl+F.

If nothing highlights, you have a scanned PDF (or a page image).

Check page count and file size on pricing.

Upload the file at https://pdf.ai/tools/ocr-pdf.

Download the result and search the first page and a later page you care about.

Keep the searchable copy. Rescan only the pages that still fail.

For what OCR is doing under the page, and when a scan is too poor to read, keep OCR PDF: Make a Scanned File Searchable next to this how-to.

If you want the file in the rest of your PDF workflow after the text layer is in place, start at PDF.ai. OCR first.