How to Make a Scanned PDF Searchable on Mac

You can't search a scanned PDF because it holds a photo of each page, not the letters themselves. Flatbed scanners, phone scanning apps and office copiers usually save pages this way unless they run OCR while they scan.

The result looks like a document but behaves like a photo album. Command-F in Preview finds nothing, Spotlight can't find the file by what it says, you can't copy an account number into an email, and screen readers have nothing to read.

Preview can't add a text layer to a PDF, so it can't make a scan searchable. Live Text in macOS lets you select text inside images, which is handy for grabbing a single phone number or address.

The catch is that nothing is written into the file. Spotlight, other apps and the person you send the PDF to still get a picture. For a document you'll search later or hand to someone else, the text has to be embedded in the PDF itself.

File Acture's OCR PDF runs Apple's Vision text recognition on every scanned page and embeds the result as an invisible text layer over the original image. The page looks exactly as before, but you can search it, select lines and copy them.

You choose the Document Language: Automatic Detection, or one of English, Turkish, German, French, Spanish, Italian, Portuguese, Russian, Chinese, Japanese and Korean. Accuracy offers Accurate, the default, which reads more carefully, and Fast, which suits long runs of clean, printed pages. Pages that already contain text are copied as they are, so a PDF that mixes typed and scanned pages doesn't end up with doubled text.

A password-protected PDF gets a Password field, and the searchable copy is protected again with the same password. The document's title, author, subject and keywords are kept, and each copy is saved with “-searchable” added to its name. You can process several PDFs in one run, and your original files stay unchanged.

OCR is only as good as the scan, so straight, sharp pages give the best text.

• Pick the language. Automatic Detection works for many documents, but choosing the language tells the recognizer what to expect, which matters most for Chinese, Japanese, Korean and Russian.
• Scan at 300 DPI. If you control the scanner, 300 DPI is a good setting for text. Much lower, and small print turns into blurry shapes that are hard to read.
• Straighten pages first. Turn sideways pages upright with Rotate Pages before you run OCR.
• Photos of documents? Put them into one PDF with Images to PDF, then run OCR on the result.
• Keep the original. The OCR copy is drawn page by page, so links, bookmarks and form fields don't carry over.
• Mind the file size. OCR adds text; it doesn't shrink images. If the copy is too big to send, run Compress PDF on it, and the text layer stays in place.

Online OCR services need your document on their servers, which matters for bank statements, medical letters and scans of ID cards. File Acture runs text recognition on your Mac, so the pages never leave it, and Pro works without an internet connection, going online only now and then to renew its license.

The free version includes 3 runs on each Mac, with up to 5 PDFs per run. For long archives of scans, see pricing.