TIFF is what scanners, fax services, document systems and archives save: a signed contract run through the office copier, a fax that arrived as an email attachment, a batch of scanned records. A PDF of the same pages is what everyone else wants: it opens in every browser and on every phone, prints at the right size, and is accepted by upload forms, courts, banks and government sites that turn TIFF away.
- Does the PDF keep all the pages of a multi-page TIFF?
- Yes, up to 2,000 pages per file, each as its own PDF page in the order the TIFF stores them. A page that cannot be decoded is left out and listed with the reason, and the rest of the file still goes into the PDF.
- Is there any loss of quality?
- Black-and-white pages, which is most scans of letters and every fax, go in as 1-bit images with lossless compression: exactly the pixels of the TIFF. Greyscale and colour pages go in as high-quality JPEG (quality 88), which keeps a scan looking as it did at a fraction of the size, though it is not pixel for pixel. The resolution is never reduced, apart from a page over 40 million pixels, which is scaled down to fit the browser's memory.
- What size will the PDF pages be?
- With As scanned, each page is its pixel size divided by the resolution in the file, so a 300 dpi scan of an A4 letter comes out A4 and a fax comes out at its paper size. A file with no resolution is taken at 96 dpi. With A4 or US Letter, every page is that paper (turned sideways for a wide page) with the picture scaled down to fit and centred, never enlarged.
- Can I make the PDF searchable?
- Not on this page: the PDF holds pictures of the pages, as the TIFF did. Open the PDF in the OCR Toolkit to add a hidden text layer so you can search and copy the words.
- How do I convert a TIFF to PDF on an iPhone or Android phone?
- Open this page in Safari or Chrome, tap the box and pick the TIFF from Files (on iPhone, save an email attachment to Files first). The PDF is saved to Downloads, or on iPhone offered to save to Files. A long fax of many pages works on a phone; hundreds of large colour scans are better done on a computer.
- Are my scans uploaded?
- No. The TIFFs are decoded and the PDFs written in this browser tab on your device; nothing is sent to this site or anywhere else, which matters for contracts, medical records and faxes.