One pile, whatever it is made of
Real folders are mixed. A visa application might hold a phone photo of a passport page as HEIC, a bank letter saved as PNG, a WebP someone forwarded from a browser and two JPEGs from an old camera. Converting each to the same format first is the chore most people expect and should not need. On this page they all go into one document in one go, in the order you put them.
The Photos step opens with a line that counts the formats in the pile — “6 JPEG · 2 PNG · 1 WebP” — and lists every file that needed a note of its own: a GIF that gives only its first frame, a CMYK JPEG whose inks had to be converted to screen colour, a file so large that a lighter copy was offered. Nothing is hidden behind a converted thumbnail; if a format changed something, the file is named and the change is said.
A worked example from our test set: one JPEG, one 1080 × 2340 PNG screenshot, a WebP, a BMP, a GIF and an iPhone HEIC went in together. The format line read “1 JPEG · 1 PNG · 1 WebP · 1 BMP · 1 GIF · 1 HEIC”, the GIF carried its first-frame note, and the saved document was 6 pages and 440 KB at the default 150 DPI ceiling — one page per file, in the order they were dropped.
How each format is written
JPEGs that need no change are copied byte for byte, which is the one way a PDF can hold a photo with no loss at all. HEIC cannot be copied — PDF has no place for its compression — so it is decoded and written once as JPEG. PNG, WebP, BMP and GIF pages are drawn once at the resolution their slot needs, as JPEG by default or losslessly if you switch that on.
If the pile is all one format, the routes for that format open better prepared: JPG to PDF counts the copies before you save, PNG to PDF opens with lossless pages, and HEIC to PDF fetches the decoder before your first file. For a portal with a file size limit, the 200 KB route starts with the target set.
Questions about image to PDF
Which image formats can go into one PDF?
JPG and JFIF, PNG, WebP, AVIF, BMP, GIF and iPhone HEIC, in any mixture. TIFF opens too, in every browser, through a reader written for this site — every page of a multi-page TIFF becomes a page. Every file is recognised by its bytes, so a PNG saved with a .jpg name is still treated as a PNG.
Are my photos uploaded?
No. Each file is decoded by the browser in this tab and written into the PDF here. HEIC files need a decoder the browser lacks, so this site sends one to you the first time a HEIC is opened — the code comes to your device, the photo does not go anywhere.
What does the PDF contain?
Pictures on pages: one image per photo, no text layer, no file names or camera details, and no title or author field. A GIF contributes its first frame only, and the builder says so next to that file.
Do the different formats come out looking different?
Only where the format forces it. JPEGs that need no change are copied as they are; everything else is drawn once at the resolution the page needs. Switch on Lossless pages on the Quality step and PNG, BMP, GIF and WebP pages are written without JPEG compression, which keeps screenshots crisp.
Can I put a PDF or a Word file in the pile?
No. This builder reads images and writes a PDF; it does not open documents. Export the pages you need as images first, then add those.