The iPhone format, on a computer that has never heard of it
iPhones save photos as HEIC by default, because it holds the same picture in about half the space of a JPEG. The cost of that saving lands on whoever receives the files: Windows needs an extension to show them, many Android galleries refuse them, and plenty of upload forms reject anything that is not JPG or PDF. The usual advice is to convert them to JPG first, which is two steps, a folder of copies and a second round of compression.
This page skips the middle step. The HEIC decoder is part of this site and is sent to your browser when you first touch the page, so it is usually ready by the time the file picker closes. Each photo is decoded in the tab, placed on its page at the paper size you choose, and written into the PDF once. The original .heic files are not changed.
A worked example from our test set: two 12-megapixel HEIC photos, 4032 × 3024 pixels each, one landscape and one portrait, went in on a desktop browser. The decoder had already arrived by the time the files were chosen, and the PDF came out as 2 pages and 164 KB: each photo on a page of its own shape, written at 1496 × 1122 pixels — 150 DPI across the A4 sheet inside a 10 mm margin.
What to expect from the pages
A HEIC cannot be copied into a PDF the way a JPEG can, because PDF has no slot for its compression, so every HEIC page is drawn from decoded pixels. With the default 150 DPI ceiling, a 12-megapixel iPhone photo on A4 is written at about 1,100 by 1,500 pixels, which reads cleanly on screen and prints well. Raise the ceiling on the Quality step for print, or lower it, or set a size, for an upload box. Portrait shots and landscape shots each get a page of their own shape unless you fix the orientation.
For a document that mixes iPhone photos with screenshots and other images, Image to PDF lists every file’s format as it goes in. If the form wants A4 with a margin, the A4 route opens set for it, and the 200 KB route opens with a size limit already typed.
Questions about HEIC to PDF
Do I need to convert HEIC to JPG first?
No. Drop the .heic files in as they are. This page decodes them in the browser and writes them straight into the PDF, so there is no intermediate folder of JPGs to make, name and delete afterwards.
Are my photos uploaded?
No. Windows and Android browsers cannot read HEIC on their own, so this page sends your browser a HEIC decoder — it starts downloading the moment you touch the page, before you pick a file. The decoder comes to you; the photos are decoded on your device and never leave it.
What does the PDF contain?
Each photo as a JPEG image on its page, decoded from the HEIC and compressed once. No text layer, and none of the photo's metadata: the location, the iPhone model and the time it was taken are not written into the file.
What about Live Photos?
A Live Photo is a still HEIC plus a short separate video. The still is what goes into the PDF; the video part is never read. If a photo looks like the wrong moment, pick a different key photo on the iPhone before exporting it.
Why is HEIC slower to open than JPG?
Because the browser has no built-in decoder for it, so the work is done by code this page brings with it. Expect a second or two per photo on a phone. Large batches are read one after another, and the progress line under the pages says how far it has got.