Convert images to PDF

PNG and JPEG files are embedded as they are, so quality is unchanged. Other formats are converted to PNG by your browser first. Only if you tick Shrink large photos are pictures wider or taller than 2000 pixels reduced to 2000 pixels: a JPEG stays JPEG at 85% quality, and a PNG, WebP, GIF or BMP picture becomes PNG with its transparency kept. That keeps a PDF of phone photos small.

No. What a photo carries besides its picture is left out of the PDF: EXIF (the GPS location, the camera, the author and the date), XMP, IPTC and comments. A JPEG's picture is still copied as it is, not re-encoded, and its colour profile is kept so colours look the same. The result says which details were left out.

Phones store many photos sideways with an orientation tag. This tool reads the tag and rotates the page content accordingly, without re-encoding the image, so the photo displays upright in the PDF. Mirrored orientations, which are rare, are redrawn upright instead, and so is a photo shrunk to 2000 px when Shrink large photos is ticked.

With Same size as each image, it decides how large the page is: a 3000-pixel-wide photo becomes a 41.7-inch page at 72 dpi, a 20-inch page at 150 dpi or a 10-inch page at 300 dpi. The pixels are the same; only the page size changes. A4 and Letter ignore it.

No. The page loads a PDF engine into your browser and every operation runs on your device. You can check this yourself in the browser's network panel: after the page has loaded there are no upload requests. Closing the tab discards the file.

No. These basic tools are free and never add a watermark. The only limits are the tool's own: images up to 16384 px on a side (Shrink large photos works on an image once it is taken, so it does not lift this). Within them, the practical limit is your device's memory.

Pictures have no password: JPG, PNG, WebP and the other formats this tool takes open as they are, so every picture is read on this device without one. The PDF it makes has no password either; to add one, open the PDF in PDF password.

Nothing you open or type. While the tab is open, the tool pages keep a short list of the steps taken in it, in the tab's session storage: the step (page opened, started, succeeded, first success, used again or failed), the tool's name, the time, how many files were used and, for a failure, an error code; never a file name, the contents of a file or your text. It holds at most the latest 200 steps, and the browser deletes it when the tab closes. The page never sends it. Where a Report a problem button is shown, you can attach the last 20 steps to your report; nothing is attached unless you tick that box. In local storage the page keeps only choices you made: a Light or Dark theme until you choose System again, the language you picked with the EN / 中文 switch if it differs from your browser's language, and this tool in your recently used list if you switched that list on at the tools page.