Convert TIFF to PDF

A TIFF to PDF converter has to understand pages first

A TIFF is not necessarily one picture. Scanners, fax systems, document archives, and imaging applications can place a chain of image file directories inside one file, with each top-level directory representing another page. Opening only the first directory may produce a perfectly valid image while quietly leaving the rest behind. This converter inventories the complete top-level page chain before it offers to make a PDF.

Every discovered page is listed in source order with a thumbnail, and its stored and display dimensions, orientation, compression, photometric interpretation, sample depth, alpha declaration and resolution are one click away under Page details. All pages are visibly selected initially. You can clear pages you do not need, but the tool will not continue with an empty selection and will never pretend that an implicit first page represents a multipage file. Each selected TIFF page becomes one PDF page in the original order. When those scans belong in a document that is already a PDF, merge the PDFs afterward and set the order of the combined pages there.

Classic TIFF is a family of storage methods, not one codec

The four bytes at the beginning identify byte order and the classic TIFF format, but they do not say how any pixel is stored. A page may be bilevel fax data, grayscale, a palette, or RGB; its strips may be raw, PackBits, LZW, Deflate, or CCITT-compressed. Supported sixteen-bit grayscale samples contain more levels than this PDF path can carry. That is why a filename check is not enough and why the receipt names the actual page characteristics rather than saying only “TIFF.”

The supported matrix is intentionally narrower than the TIFF specification. Verified classic files use strips and contiguous samples with bilevel, grayscale, RGB, or palette pixels. BigTIFF, tiled or planar pages, signed or floating-point samples, JPEG-compressed TIFF, Predictor 3, CMYK, YCbCr, Lab, and unknown combinations receive a typed unsupported result. A plausible preview made by guessing at an unfamiliar layout would be more dangerous than a useful refusal, especially for a scanned record whose missing marks may not be obvious.

Orientation, alpha, and sixteen-bit source pixels

TIFF orientation has eight values, including mirrored rotations. The converter applies the declared transform to the pixels and page dimensions, so the PDF does not depend on a metadata tag that another reader may ignore. The finished PDF is reopened to verify its page count and page boxes; the receipt does not mislabel that structural check as a pixel comparison.

Alpha is accepted only when the TIFF declares associated or unassociated ExtraSamples. Associated alpha is unpremultiplied before compositing; undeclared extra channels are not guessed to be transparency. PDF has a deliberate opaque result here: declared alpha is flattened on white and the receipt says so. Supported unsigned sixteen-bit grayscale samples are scaled to eight bits and the reduction is reported before conversion and on the receipt. The PDF is therefore a readable raster document, not a bit-exact archival replacement for the TIFF.

What the PDF preserves, and what stays in the source

The visible page pixels, their upright dimensions, the chosen page set, and page order are the product contract. Each selected page is embedded as an upright PNG raster at its display pixel dimensions. Bilevel and grayscale pages use DeviceGray rather than being expanded to RGB. With Fit each page, a valid TIFF resolution determines the PDF page box; if it is absent or invalid, the fallback is 96 dpi, and a scan without that tag starts on Letter instead, because a guessed 96 dpi rarely gives a page anyone wants to print. Letter and A4 place each image upright and as large as a half-inch margin allows, turning the sheet for a wide page. Embedded ICC profiles are not applied or carried into the result. GeoTIFF coordinates, EXIF fields, private tags, thumbnails, masks, and image pyramids do not become PDF metadata or extra pages. Auxiliary SubIFDs are counted and named as auxiliary so their existence cannot be confused with document pages.

Keep the original TIFF when color-managed production, geospatial meaning, high bit depth, private scanner tags, or evidentiary preservation matters. The new file is an ordinary image-based PDF: it does not perform OCR, create selectable text, certify PDF/A, or prove that a digital archive and its source are equivalent. To extract one chosen page as an image instead, use TIFF to PNG for alpha and lossless 8-bit output, or TIFF to JPG for a smaller photographic delivery copy.

The finished document is checked before download

The result receipt reports source pages, selected pages, output pages, applied orientation, sample-depth conversion, alpha or background treatment, color-profile handling, discarded metadata, and file size. The generated bytes are opened again before the download appears. Page count and page boxes must agree with the plan; the receipt also prints every actual page size in points and inches. A file that merely begins with a PDF signature is not sufficient evidence, but this built-in check does not claim to compare output pixels.

Need to change the selection? The decoded page inventory remains available, so another run does not require choosing the TIFF again. After the page inventory is known, a very large scan receives local memory advice based on pages and decoded pixels rather than compressed file bytes. Work runs in a cancelable worker with real byte and page progress, and an older job cannot overwrite a newer result.

Local conversion without an upload

The TIFF bytes and generated PDF stay in this browser tab. They are not placed in the URL, browser storage, analytics, or a conversion API. File, drop, and a clipboard TIFF file use the same byte-based parser; no extension is trusted as proof. The local-processing guide explains how to inspect the network boundary yourself. Going the other direction is not a switch on this page: PDF-to-TIFF needs an encoder and compression choices of its own and is outside this verified route.