Both PDF and TIFF are used for scanned documents, and both can preserve image quality well. The difference comes down to what you need to do with the file afterward. TIFF is a pure image format. PDF is a document container that can hold images, text, and metadata. That distinction determines which one makes more sense for your use case.
What TIFF Is Good At
TIFF (Tagged Image File Format) was designed for high-quality image storage. It supports lossless compression, meaning no image data is discarded when the file is saved โ what the scanner captured is exactly what the file contains. TIFF also supports multiple pages in a single file (multi-page TIFF), high bit depth for color accuracy, and various compression methods including LZW and ZIP.
It's the preferred format in industries where image fidelity is paramount: medical imaging, professional photography, print production, and some archival workflows. If you're scanning original artwork, historical documents for museum archives, or materials that will be used in professional print production, TIFF gives you the highest-quality image container available.
What PDF Does That TIFF Can't
PDF can contain much more than images. A scanned document saved as PDF can have an OCR text layer added, making the text searchable and copyable even though the underlying file is still a scan. TIFF has no mechanism for this โ it's pixels only, no text layer. For any scanned document you might want to search, reference, or extract text from, PDF wins.
PDF is also a multi-page format natively, with consistent viewer support everywhere. A 50-page scanned document is one PDF file that opens in any browser or device. A 50-page TIFF is either one large multi-page TIFF (which many viewers don't handle well) or 50 separate TIFF files. For document workflows โ sharing, reviewing, filing โ PDF is far more practical.
PDF also supports metadata, bookmarks, hyperlinks, digital signatures, and access controls. A scanned contract in PDF can be signed electronically. A scanned TIFF cannot.
File Size Comparison
Uncompressed TIFF files are large โ a single A4 page scanned at 300 DPI in color produces a 25MB uncompressed TIFF. LZW-compressed TIFF brings that down to around 5-8MB per page. PDF using JPEG compression for the same scan might be 300KB to 1MB per page, depending on quality settings.
PDF with lossless compression (like JBIG2 for black-and-white documents) can match or even beat TIFF file sizes while preserving the same quality. For most scanning use cases, a well-compressed PDF is both smaller and more functional than the equivalent TIFF.
Which One Do You Actually Need?
For business documents โ contracts, invoices, correspondence, forms, reports โ PDF is the right choice in almost every case. It's searchable after OCR, universally supported, easier to share, and integrates with every document workflow tool available. Use a Scanned PDF format for anything that needs to function as a document.
For images that need to be treated as images โ artwork, photographs, materials going into professional print workflows โ TIFF is appropriate when maximum fidelity and lossless storage are the priority, and the file will be handled by people and systems that specifically support TIFF.
Some specialized archiving standards (like those used by certain government and library systems) specifically require TIFF for image archiving. If you're working in one of those contexts, the format is usually mandated. For everyone else, PDF handles scanned documents better in practice and comes with none of the compatibility headaches that multi-page TIFF files tend to create.
Converting Between the Two
If you have TIFF files that need to be PDFs, conversion is straightforward. Most image editing software can open TIFF and export as PDF. Browser-based tools handle single-page TIFFs easily; multi-page TIFFs may need desktop software depending on the tool. The reverse โ PDF to TIFF โ is less commonly needed but works the same way through export or conversion tools.
If your scanned PDFs don't have searchable text yet, running OCR afterward is quick. WukongPDF's OCR tool adds a text layer to existing scanned PDFs without changing the image quality โ the scan stays as-is, and the text layer is added on top, making the whole document searchable.