PNG → PDF
PNG to PDF converter
Drop your PNGs and get one PDF, a picture per page, in the order you added them. The document is built in this tab, so screenshots, diagrams and scans stay on your machine.
PDF pages have no alpha channel, so see-through pixels are flattened onto white before anything is stored. Every remaining pixel goes in losslessly — no compression loss is added, and no background colour can be chosen here.
How to convert PNG to PDF
Add the PNGs
Drop one or several PNG files on the box above, or pick them from disk. Each file becomes a page, in the order it was added, so put the title image in first.
Choose the frame
A4, US Letter or fit-to-image, plus the margin in points. A 36-point margin is half an inch; 0 points fills the page with the picture.
Download and check
Save the PDF and open it at 100% once. Lossless storage keeps every pixel, so a screenshot should look identical to the PNG it came from — shape, edges and all.
How a PNG becomes a PDF page
PNG stores pixels losslessly with an optional alpha channel and is already deflated on disk; a PDF page stores drawing instructions and can carry an image with a lossless filter of its own. Getting from one to the other means decoding the PNG to raw pixels, resolving the alpha channel, and compressing those pixels again for the page. Every step is lossless, so no image detail is discarded along the way.
What goes missing is transparency: a PDF page has no alpha, so each see-through pixel is resolved to white before the pixels are stored. What you pay is size, because a lossless format has little room to shrink a photograph — a PDF built from camera PNGs lands at roughly the size of the PNGs themselves. Screenshots, diagrams, logos and type keep their edges intact, which is exactly where a JPEG round-trip would show ringing.
PNG to PDF questions
Are my PNGs uploaded anywhere?
No. The PNG is decoded and re-compressed inside this tab and the PDF is saved from memory to your disk, so nothing about the document reaches a server — not the pixels, not the file name. The page needs no account and no network connection after it has loaded.
Where did the transparent background go?
PDF has no alpha channel at page level, so transparency has to be resolved before the pixels can be stored, and this converter resolves it to white. There is no background-colour option on this page, so if the see-through areas are part of the design, keep the PNG as the master copy.
Should I pick A4 or US Letter for printing?
A4 is 210 by 297 mm, which is 595 by 842 points, while US Letter is 612 by 792 points — 8.5 by 11 inches. Match the paper your printer actually holds: most of the world prints A4, North America prints Letter, and fit-to-image avoids the question by giving every page the size of its own picture.
What is the largest PNG this tool will take?
64 MB per file, with the number of pages limited only by the memory your browser gives the tab. Lossless pages of large screenshots add up quickly, so when a PDF only has to be viewed, converting the PNGs to JPG first produces a far smaller document.