How to convert JPG to PDF — every option explained

Turning photos into a PDF is how a pocketful of expense receipts becomes a claim, how a day of inspection shots becomes a report, and how a handful of scans becomes one document anyone can open. The catch with most online converters is twofold: your photos take a trip to a stranger’s server, and they usually come back re-compressed. This guide covers the conversion that stays on your machine, then the decisions most guides gloss over — page size, margins, and what actually preserves image quality.

Convert JPG to PDF in your browser, step by step

The tool for the job is the JPG to PDF converter on this site. It runs entirely in your browser — the photos you add are never uploaded, and it keeps working with the network disconnected.

1. Open the converter and drop your JPG files anywhere on the page, click to browse, or paste them straight from the clipboard.
2. Put the list in order. The file list is the page order — each image becomes exactly one page — so use the arrows to move photos up or down until the document reads the way you want.
3. Choose a page size: A4, US Letter, or “match image size”. Add a margin between 0 and 25 mm if the file is headed to a printer.
4. Click Convert to PDF. The document is assembled on your device — images embedded as-is, a progress bar tracking the work — and one more click saves it.

Photos from the same shoot convert best in a single pass: the order you set becomes the document’s flow, and there is nothing left to fix afterwards.

Why image quality survives the conversion

This is the detail that decides whether printed pages look right. A JPEG file is already compressed image data, so a converter has two options: embed that data byte-for-byte, or decode the image and re-encode it. Most converters re-encode — quietly spending quality on a trip your photos never needed.

This tool embeds. The JPEG data goes into the PDF container untouched: no recompression, no added artifacts, nothing re-sampled. Whatever quality a photo had going in is exactly what the PDF has inside — a 12-megapixel photo prints like a 12-megapixel photo.

A related nicety: files are validated by content, not by name. A photo carrying the wrong extension still converts, because the tool reads the file’s magic bytes rather than trusting its label — and a document that only pretends to be an image is rejected with a clear message instead of a broken page.

A4, Letter, or the image’s own size

Page size is where conversions go wrong, because the three settings serve different destinations.

On A4 or US Letter, each image is scaled to fit and centered on a standard page, and the orientation — portrait or landscape — is chosen automatically, per image. That last part matters more than it sounds: a mixed batch of upright and sideways photos needs no manual sorting, because every page picks its own orientation.

“Match image size” takes the other road: the page adopts each image’s exact dimensions, with zero rescaling. This is the right choice for documents that will live on a screen — nothing is stretched, and no white borders appear around photos with non-standard proportions.

Margins, from 0 to 25 mm, exist mostly for printers, since consumer hardware cannot print to the very edge of a sheet. For a document that will only ever be read on screen, leave the margin at zero.

One document from mixed sources

Real projects rarely hand you a clean pile of JPGs. If PNG images are in the batch, do not convert them to JPG just to fit the tool — that would spend quality for nothing. Run them through the same engine on the PNG to PDF page, then merge the two PDFs into one document.

If the finished file travels by email, give it a pass through Compress PDF — with one honest caveat: documents built from photos shrink surprisingly little, because JPEG data is already compressed and is embedded without re-encoding. The pass never grows the file, but a photo PDF starts close to its floor. Trimming the pages that did not make the cut helps more than any setting — delete them before compressing.

When a desktop app makes more sense

Two honest cases for installing software. First, format conversion at scale: iPhone photos saved as HEIC are not JPG, and this converter will not take them — exporting from the Photos app or a desktop batch converter is the right way to prepare a whole library before building the PDF. Second, very large batches: the practical ceiling of any browser tool is your device’s memory, since every image is decoded locally. A phone is happiest with a few dozen large photos per document; a desktop machine with roomy memory handles archives of hundreds in one go.

For everything shorter — which is nearly every real document — the browser wins on every axis that matters: nothing to install, nothing to update, and photos that never leave your device.