Twenty photos from a site visit, a dozen receipts for an expense report, a folder of screenshots for a bug ticket — converting a batch of images into one PDF sounds like the same job as converting a single image, but it isn't. The single-image conversion has exactly one real decision: page size. A batch has several. What order do the pages land in? How do tall phone photos, wide screenshots, and scans coexist in one document? Will the result be something a person can navigate? JPG to PDF does all of it in your browser, with nothing uploaded anywhere — this guide is about the decisions, not the clicks.
It deliberately skips the basics: formats, quality, and file size are covered in How to Convert JPG to PDF, and the PNG-versus-JPG source question in How to Convert PNG to PDF. What follows is strictly the batch workflow: ordering, mixed collections, page size at scale, and page numbers.
Get the order right before you convert
The most common batch mistake is assuming the tool knows what order your pages should be in. It doesn't. The order you arrange the images in is the page order of the final PDF, full stop. What you do before converting either pays off or comes back to bite you, and there are three workable strategies.
Shoot in order. Cameras name files with incrementing numbers, so a burst captured in sequence sorts correctly. When you're photographing whiteboard frames, walking a site, or working through the pages of a paper document, shooting in reading order is the cheapest sorting you will ever do.
Name files sortable. If you're renaming by hand, zero-pad the numbers: 01, 02 … 10. Unpadded names sort as 1, 10, 11, 2 — eleven files in the wrong order from one missing digit. If the batch has natural sections, prefix by section: 01-cover, 02-map, 02a-legend. Thirty seconds of renaming saves the full manual reorder later.
Reorder in the tool. Drop everything in, then drag the thumbnails with the arrows until the strip reads like the document you have in your head. Treat this as the final check rather than the plan — it's free, but it's the slowest place to discover your files were named badly.
Handling a mixed collection
Real batches are rarely uniform. Phone photos arrive as JPG, screenshots as PNG, and plenty of documents mix both. The tool takes JPG/JPEG and PNG, and you can mix the two in the same document — so there's no pre-conversion step to a common format.
Mixed orientations — portrait photos next to landscape screenshots — are handled rather than punished. With page size set to match each image, every page simply takes its image's own dimensions and orientation: a portrait page followed by a landscape page is a normal, correct document on screen. With a uniform page size, each image is centered with its aspect ratio kept, and wide images automatically get a landscape page so nothing is squeezed.
Mixed resolutions settle the same way. A 12-megapixel photo next to an 800-pixel-wide screenshot is a lopsided document: on match-the-image sizing the pages visibly differ; on a uniform A4 or Letter page both sit centered at natural size — the screenshot stays small and sharp rather than blown up into blur.
Choosing a page size for a mixed batch
The batch version of the page-size decision has a tiebreaker the single-image version doesn't: consistency. One page only has to suit its image; thirty pages read in sequence also have to feel like one document.
Match each image when the PDF will live on screen — viewing in a reader, attaching to a ticket, archiving. Every page is exactly its image: nothing scaled, nothing cropped, no margins. This is the honest choice for fidelity, and for mixed batches it honestly produces a document whose page size changes from page to page.
Uniform A4 or US Letter when the PDF will be printed or filed alongside other documents. One paper size for the whole batch, a modest margin, every image centered at its natural size. For a batch mixing tall receipts and wide screenshots, uniform pages are what make the result feel like a document rather than a pile — and it prints without surprises.
Either way, images are never stretched to fill a page — a small image on a Letter page stays at its original resolution, centered. The conversion doesn't invent pixels.
Page numbers for documents people will reference
Batch scale is where page numbers earn their keep. The tool can add a simple n / total marker at the foot of each page, and the moment your document crosses into double digits, that marker starts doing real work: "see page 17" only functions if page 17 is labeled. An inspection photo log, a receipt bundle that accounting will cite entry by entry, a step-by-step screenshot guide — all get easier to talk about when the pages are numbered.
It's a toggle, and it ships off — a two-page document doesn't need bookkeeping. The rule of thumb: turn it on when the page count is double digits, or when someone else will need to reference pages back to you.
How big will the PDF be?
The arithmetic is honest and worth doing before you convert: each image is embedded as-is, with no recompression and no resizing, so the output PDF is roughly the sum of its inputs. Twelve photos at four megabytes each produce a PDF somewhere around forty-eight megabytes. The format doesn't shrink your images, and the tool won't silently degrade them either.
The limits that actually exist: 100 MB per image, and no fixed cap on how many images you can combine — because processing happens locally in your browser, the practical ceiling is your device's memory. Several dozen pages is routine on an ordinary laptop.
If the destination has a size cap — an email attachment limit, say — the right order of operations is to reduce the images first and then convert, or to run the finished PDF through Compress PDF before sending.
The batch workflow, start to finish
- Collect the images and rename them so they sort in the order you want.
- Open JPG to PDF and drop the whole batch in.
- Drag with the arrows until the thumbnail strip reads like the document.
- Pick a page size: uniform A4 or US Letter for printing and filing, match-each-image for screen fidelity.
- Switch on page numbers if the document is long enough that someone will cite pages.
- Convert and download — one PDF, in the order you set, images sharp as the originals.
The whole run happens on your machine. That's not a slogan, it's the reason there's no file-count cap to read about: dozens of photos being assembled into one document is your device's business and nobody else's.