Photos to one PDF: page size, margins and file size tested

The page size you pick for a photo PDF changes the file by less than a kilobyte. Seven phone photos made a PDF of 20,952,152 bytes with every page the size of its picture, 20,952,350 bytes on A4 and 20,952,261 on Letter. What does change the size is whether each photo goes in as it is. And one of the seven was carrying 1.9 MB of extra pictures that no viewer shows.

Seven phone photos, one PDF

On 24 September 2026 we took seven photos from Wikimedia Commons that still had their camera details and a GPS position: two from an iPhone 13, two from an iPhone 15 Pro, two from a Pixel 7 and one from a Galaxy S22. Together they came to 27.6 MB. We put them through our JPG to PDF tool in Chromium 153, one PDF per photo and one with all seven, at each page size (Same as picture, A4, Letter) and each margin (None, Small, Large). Then we pulled every picture back out, compared it byte by byte with the photo that went in, and ran exiftool 13.55 on both the PDFs and the pictures.

Seven Wikimedia Commons phone photos through WipeTheAI JPG to PDF in Chromium 153, 24 September 2026. PDF sizes are for one photo per file; the page size moved them by under 50 bytes each (n=7 photos)
Photo	Photo file	Its PDF	How it went in
iPhone 13, 4032 × 3024	3.74 MB	3.74 MB	Untouched
iPhone 13, 2268 × 4032	2.15 MB	2.14 MB	Untouched, HDR brightness map kept
iPhone 15 Pro, stored on its side	6.65 MB	4.92 MB	Saved again as JPEG
iPhone 15 Pro, stored upside down	5.43 MB	4.56 MB	Saved again as JPEG
Pixel 7, 3072 × 4080	6.24 MB	2.21 MB	Untouched; 1.89 MB of extra pictures left out
Pixel 7, 3072 × 3071	2.07 MB	2.07 MB	Untouched
Galaxy S22, 2629 × 1609	1.32 MB	1.32 MB	Untouched
All seven in one PDF	27.6 MB	20.95 MB	6.4 seconds on our test Mac

Five of the seven went in untouched. The compressed picture inside the PDF is the camera’s own, byte for byte; only the blocks of camera details in front of it are gone. Each page adds about 800 bytes of PDF around the photo, so a PDF of photos is roughly as big as the photos themselves.

The two iPhone 15 Pro photos weren’t. Phones often store a picture sideways and add a note saying which way up to show it. Viewers read the note; a PDF has no such note, so our tool turns those pictures upright and saves them once as a high-quality JPEG. They came out 26% and 16% smaller, a second round of compression you won’t see at normal size, but not the original picture any more.

The Pixel photo that held three more pictures

The 6.24 MB Pixel 7 photo was a portrait-mode shot. After the end of the photo itself, the camera app had stored a second copy of the scene at 2024 × 2688 that it labels the original, a depth map of how far away each part of the scene was, and a confidence map for that depth: 1.89 MB in all. Each of the three carries its own camera details, including the date and time the photo was taken, 30 December 2022 at 08:51:16.

Our first run put all of it into the PDF. The tool removed the photo’s own camera details and the index that lists the extra pictures, then copied everything after that point, extras included. exiftool, run on the picture we pulled back out, reported nothing but a colour profile, because with the index gone it had no reason to look further. The date was still in the PDF for anyone who searched its bytes. We fixed the cleaner the same day: it now stops at the end of the photo unless the file lists an HDR brightness map there, which iPhones use to show the photo brighter on HDR screens. That page went from 4.10 MB to 2.21 MB. The same fix applies to our EXIF remover, which uses the same cleaner.

Chromium’s own Save as PDF, given a page showing the same photo, made a 6.25 MB PDF with the whole file inside it: the GPS position, the phone model and the three extra pictures.

Same as picture, A4 or Letter

Our tool sizes a picture at 96 pixels per inch, the usual screen density. With Same as picture, a 4032 × 3024 phone photo gets a page 42 × 31.5 inches (107 × 80 cm) and the iPhone 15 Pro photos a page 44.6 × 59.5 inches. On screen that makes no difference, since PDF readers fit the page to the window. On paper, the print window has to scale every page down, and anyone who asked you for an A4 or Letter file gets a 42-inch page.

How much of the page each photo covers, and how many photo pixels land on each printed inch, with the Small margin (20 points, 7 mm). Worked out from the drawing instructions in our PDFs, 24 September 2026
Photo shape	Same as picture	A4	Letter
4:3, landscape (iPhone 13)	42 × 31.5 in	82% of the page, 392 px/in	88%, 386 px/in
3:4, upright (Pixel 7)	32 × 42.5 in	82%, 398 px/in	88%, 391 px/in
9:16, upright (iPhone 13)	23.6 × 42 in	72%, 362 px/in	66%, 386 px/in
Square (Pixel 7)	32 × 32 in	62%, 398 px/in	68%, 387 px/in
Cropped, 2629 × 1609 (Galaxy S22)	27.4 × 16.8 in	79%, 236 px/in	71%, 252 px/in

Every full-size phone photo lands at over 360 pixels per inch on either paper size, and even the cropped Galaxy photo at 236, so the choice between A4 and Letter is about white space more than sharpness. Letter suits the 4:3 and 3:4 photos most phones take: 88% of the page against 82% on A4. A4 suits tall 9:16 shots. Wide pictures get a landscape page on their own. Going from the Small to the Large margin (40 points, 14 mm) takes a 4:3 photo from 82% of an A4 page to 71%; None fills 94% but leaves no border for a printer that can’t print to the edge.

The iPhone photos use the wider Display P3 colours. Their colour profile stays inside the picture, and when we drew the PDF page with pdf.js, the viewer built into Firefox, its colours matched the photo shown directly: an average difference of 0.5 on the 0 to 255 scale, against 1.4 if the profile had been ignored. macOS drew the page in Display P3 as well.

PNG files are a different case

A PNG keeps every pixel in the PDF, but it is packed again rather than copied, and for photos our packing is less compact than PNG’s own. A 165 KB screenshot of one of our pages came out as a 133 KB PDF. The square Pixel photo above, saved as an 11.9 MB PNG, came out as a 17.7 MB PDF, 48% bigger. If your photos are PNGs, convert them to JPG first with PNG to JPG, or run the PDF through Compress PDF afterwards.

For a PDF you will send or upload, pick A4 or Letter, keep the Small margin, and check the order before you save. Same as picture is for a PDF that only ever lives on a screen. To check what a PDF you already have is carrying, pull its pictures out with Extract images from PDF; our earlier test of six other PDF makers found four that keep the GPS position.