How to combine images into one PDF

For turning a pile of phone photos of paperwork into one document somebody will actually accept.

Combine them

1. Open the converter and go to the "Convert a file" tab.
2. Add all the images together. They appear in the order they will be placed, one per page.
3. Click Combine in the bar that appears.
4. combined.pdf downloads, with each image centred and fitted to an A4 page.

Open the tool

iPhone HEIC photos work here too, and are decoded automatically. A single image converts to a single-page PDF using the ordinary PDF output instead.

Getting the order right

Images are placed in the order the cards appear in the list, which follows the order your file picker supplied them. Selecting a whole folder usually gives alphabetical order, so naming files 01.jpg, 02.jpg and so on is the reliable way to control sequence. Note that 10.jpg sorts before 2.jpg — hence the leading zeros.

Quality and file size

Images are embedded as JPEG, since that is what keeps a photo-based PDF to a sensible size. Two settings under Image and page settings control the result:

• JPEG quality — High is a good default. Drop to Medium if the PDF needs to go through an email attachment limit.
• Max width — leave blank for full resolution. Setting something like 2000 pixels dramatically reduces size for documents that only need to be readable, not archival.

The pages come out as A4

Every image is fitted inside an A4 page with a small margin, preserving its aspect ratio — nothing is stretched or cropped. Landscape photos sit centred with space above and below. This keeps the document printable anywhere, which is usually the point of making a PDF in the first place.

The other direction

To go the other way — a PDF back into images — see converting a PDF to images. To join existing PDFs rather than images, see merging PDF files.