JPG to PDF Converter

Building a PDF out of images is how scans, receipts, signed pages and photo collections become documents that can be attached, filed and printed reliably. This JPG to PDF converter combines your images into a single PDF document entirely in your browser, so you can convert JPG to PDF online free with full privacy. It is also the format that survives every email system and portal without complaint.

JPG to PDF page sizes and what they mean

PDF measures pages in points, at 72 points per inch:

Choosing a standard size rather than “fit to image” is what makes a JPG to PDF document printable. A PDF whose pages are the exact dimensions of your phone photos will print unpredictably, because the paper in the tray is A4 or Letter and something has to give. In Fit to image mode each sheet is the image's own pixel dimensions plus twice the margin, so setting the margin to zero gives you a page that is exactly the image, with no scaling applied at all.

The figures above are what the page-size menu shows, rounded to whole points; the values actually written are 595.28 × 841.89 for A4, 841.89 × 1190.55 for A3 and 419.53 × 595.28 for A5, with Letter and Legal already exact at 612 × 792 and 612 × 1008.

How each image is placed when you convert JPG to PDF

There is deliberately no fill or stretch mode here, because both destroy information. Each image is scaled by whichever of two factors is smaller — the one that fits its width into the printable area, or the one that fits its height — and then drawn at that single scale. Proportions are locked, so nothing is cropped and nothing is distorted.

Two consequences follow. The first is white space. A portrait phone photo on a landscape A4 page sits in the middle with margins either side, and that is the correct result: the alternative is a subject pulled sideways, or a signature quietly cropped off the edge of the sheet. If you would rather the page matched the photo, choose Fit to image and the sheet is built around the image instead of the image being fitted to the sheet.

The second is that the scaling runs in both directions. An image smaller than the printable area is enlarged until it fills as much of that area as its aspect ratio allows, which is what lets a modest phone snapshot cover a whole A4 page — and what makes a 300-pixel thumbnail look soft on paper. If a small image should stay small, raise the margin until the printable area is close to the size you actually want.

Margins and DPI for JPG to PDF conversion

A 0.5-inch margin on A4 gives a printable area of about 523 × 770 points. An image 1600 pixels wide fitted into that area lands near 220 DPI, which prints cleanly. Below roughly 150 DPI, text in the image starts to look soft on paper — so if print quality matters, source images of at least 1200 pixels on their short edge.

JPG to PDF centring, corners and captions

Centre images on the page is switched on by default. Turn it off and every image is pinned to the margin at the bottom-left of its sheet, because that is where a PDF page's coordinate origin sits — what looks like the top-left corner of the printed page is the point (0, height) in the file's own terms. Pinning is useful when a stack of oddly shaped images should all share one corner; centring is what you want for almost everything else.

Add a filename caption prints the source filename in 8-point grey Helvetica along the bottom margin of each page. Turning it on reserves 18 points of the sheet for the caption row, so the image area shrinks by that much to make room. It is the difference between a photo book and an evidence bundle: twenty interchangeable images become twenty labelled ones.

What your JPG to PDF document looks like

One image produces a PDF named after that image; several produce images.pdf. Your JPG to PDF document is stamped as it is built — producer Collabs Tool, creator Collabs Tool — JPG to PDF, and a title taken from the first filename — so it identifies itself sensibly in a document management system instead of arriving anonymous. The summary strip reports the page count, the final file size, the page size and the orientation setting.

Formats beyond JPG and PNG are handled on the way in. JPEG and PNG are embedded as they are in the JPG to PDF output, since pdf-lib can place both natively without recompressing them. Anything else — WebP, GIF, BMP, AVIF, SVG, or a file whose extension lies about its contents — is drawn onto a canvas flattened with white and re-encoded first: as JPEG for photographs, and as PNG for SVG and other line art, so no lossy artefacts are introduced into hard edges. That re-encode step is also why the finished PDF opens happily in readers that have never heard of WebP.

Create PDF from JPG images with full privacy

This JPG to PDF converter is designed for anyone who needs to create a PDF from JPG, PNG or WebP images without uploading them to a remote server. The entire image to PDF conversion runs in your browser using pdf-lib, so your photos, scans and receipts never leave your device. Whether you are combining a handful of phone photos into a single PDF or building a multi-page document from scanned pages, this JPG to PDF tool handles the job locally. You can reorder pages by dragging thumbnails, choose from five standard page sizes or fit to image, and set margins to control the final layout. The result is a professional-looking PDF that embeds every image directly, so the document is self-contained and opens identically on any device. Converting JPG to PDF has never been simpler — just add your images, arrange them, and download your JPG to PDF document in seconds.