How do I make a PDF searchable for free?

Upload your PDF to a free OCR tool like PDF24, iLovePDF, or Google Drive. The tool adds an invisible text layer over the scanned image so you can use Ctrl+F to search. On iPhone, the [Scanjet app](https://scanjet.app) does this offline in seconds — no file ever leaves your device.

What is the difference between a searchable and non-searchable PDF?

A non-searchable PDF is essentially a photograph of a page — the words look like text but are just pixels. A searchable PDF has a hidden text layer added by OCR, so you can search, select, copy, and highlight the content. See our guide to [extracting text from PDFs](/blog/extract-text-from-pdf/) for more.

Can I make a PDF searchable on my iPhone?

Yes. The [Scanjet app](https://scanjet.app) scans paper documents directly into searchable PDFs using OCR in 23 languages — fully offline, so your documents stay on your device.

Does making a PDF searchable change how it looks?

No. OCR adds an invisible text layer underneath the original image. Your PDF looks identical — same layout, fonts, and graphics — but the text is now machine-readable and Ctrl+F-searchable.

What resolution is needed for accurate OCR?

300 DPI is the minimum for reliable OCR accuracy. Below that — especially on faded or crumpled pages — character recognition degrades noticeably. Most modern smartphone cameras capture well above 300 DPI by default.

Make PDF Searchable: Best Tools and How They Compare

Pressing Ctrl+F on a scanned PDF and finding nothing is one of the most common document frustrations. This guide compares the best free and paid tools to make any PDF searchable — online, on desktop, and straight from your phone.

Frequently Asked Questions

How do I make a PDF searchable for free?: Upload your PDF to a free OCR tool like PDF24, iLovePDF, or Google Drive. The tool adds an invisible text layer over the scanned image so you can use Ctrl+F to search. On iPhone, the [Scanjet app](https://scanjet.app) does this offline in seconds — no file ever leaves your device.
What is the difference between a searchable and non-searchable PDF?: A non-searchable PDF is essentially a photograph of a page — the words look like text but are just pixels. A searchable PDF has a hidden text layer added by OCR, so you can search, select, copy, and highlight the content. See our guide to [extracting text from PDFs](/blog/extract-text-from-pdf/) for more.
Can I make a PDF searchable on my iPhone?: Yes. The [Scanjet app](https://scanjet.app) scans paper documents directly into searchable PDFs using OCR in 23 languages — fully offline, so your documents stay on your device.
Does making a PDF searchable change how it looks?: No. OCR adds an invisible text layer underneath the original image. Your PDF looks identical — same layout, fonts, and graphics — but the text is now machine-readable and Ctrl+F-searchable.
What resolution is needed for accurate OCR?: 300 DPI is the minimum for reliable OCR accuracy. Below that — especially on faded or crumpled pages — character recognition degrades noticeably. Most modern smartphone cameras capture well above 300 DPI by default.