How to convert PNG to PDF (screenshots and logos)
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Contents
To convert PNG images to PDF, open PNG to PDF, add your PNGs, put them in order, press Create PDF, then press Download PDF. Each PNG becomes one page of the PDF. It is made in your browser, so the images stay on your device, and each one can be up to 25 MB.
PNG is the format of screenshots, charts and logos because it keeps every pixel, and the PDF keeps them too. With Max file size left at No limit, a PNG goes into the PDF with lossless compression, never as a JPEG, so small interface text and sharp edges come out as they were.
What is particular to PNG is covered below: what happens to see-through areas, why the PDF can be larger than the images, and how big a screenshot's page turns out.
Step by step
- 1Open the PNG to PDF tool and drop your PNGs on the box at the top of the page, or click it to pick them. JPG, WebP, GIF, and BMP images can go into the same PDF.
- 2Check the order under Image order. Screenshots named as one numbered set, such as Screenshot (1).png, Screenshot (2).png, and Screenshot (10).png, are put in the order of their numbers, with a note saying so; press Keep drop order to undo that. Move an image with the up and down arrows on it.
- 3For screenshots, choose Fit to image under Page size, so each page is the size of its image. For pages you will print, keep a paper size and set the Orientation and Margin.
- 4Leave Max file size on No limit to keep every pixel. Choose a size only when a form limits the file, because that saves the images again as JPEGs.
- 5Press Create PDF, then Download PDF. The file is named after your first image, so chart.png becomes chart-pdf.pdf.
What happens to transparent areas
Each page is filled with white before the image is drawn on it. A PNG with an alpha channel keeps it in the PDF as a soft mask, so its see-through areas show the white page, and soft edges, such as a logo's smoothed outline or a drop shadow, blend into the white. A PNG whose pixels are all fully opaque is stored with no mask.
So a white logo, or white text, on a transparent background comes out white on white and seems to vanish. There is no background colour setting: give such artwork a coloured background in your image editor and export it again before converting it.
If you choose a Max file size and the PDF comes out bigger than it, the images are saved again as JPEGs, which cannot be see-through, so transparent areas are filled with white first, the colour of the page, and the line under the result says so.
Why a PDF of PNGs can be larger than the PNGs
Inside the PDF every PNG is stored as eight-bit full colour, compressed without loss but without PNG's own row filters. A palette PNG, the compact kind with a short list of colours that many programs save icons and simple charts as, and a greyscale PNG are expanded to full colour, so the PDF can be much larger than the files you added.
A PNG with sixteen bits per channel is cut down to eight, the one change made to its pixels. If the PDF must be smaller, Max file size trades sharpness for size; with screenshots full of small text, try the largest size the form allows.
How big a screenshot's page is
The image is laid out at one point per pixel, and a point is 1/72 of an inch, so screenshots are large on paper. On the default US Letter (8.5 × 11 in) page with its 0.5 in margin, a screenshot 1,920 pixels wide is shrunk to 7.5 inches across. No pixel is thrown away by that, so zooming in on the PDF still shows the detail. With Fit to image, the same screenshot gets a page about 27.7 inches wide, which reads well on screen; to print it, use your printer's fit-to-page setting.
A small image is never enlarged, so an icon stays icon-sized on a paper page. A long scrolling capture stays one image on one page: it is not cut across several pages. On a paper size it is shrunk to the page's height, so choose Fit to image to keep it readable. Even then a page side cannot pass 200 inches, and a longer capture is scaled down to fit that. Any DPI value stored in the PNG is ignored.
Common questions
Will my PNG lose quality in the PDF?
Not with Max file size at No limit: the pixels are stored without loss, never as a JPEG. The only change is that a sixteen-bit PNG is cut down to eight bits per channel. A Max file size the PDF is over is the exception you choose: then every image is saved again as a JPEG, smaller and softer, until the PDF fits.
Does PNG to PDF keep transparency?
Yes, as a soft mask over a white page, so see-through areas look white on screen and in print, and soft edges blend into the white. A Max file size that has to save the images again fills those areas with white instead.
Why is my PDF larger than my PNG files?
Because each PNG is stored as full colour in the PDF. A palette or greyscale PNG is expanded to full colour on the way, which can make the PDF far heavier than the files you added.
Can I put PNG and JPG images in one PDF?
Yes. A JPG keeps its original JPEG data. WebP, GIF, and BMP images are decoded by your browser and saved again, as a PNG when they have transparency. HEIC, TIFF, and AVIF images are turned away when you add them. To add the screenshots to a PDF you already have, convert them first, then join the two with Merge PDF.
Are my images sent to a server?
No. The PDF is made in your browser tab; the images are not sent to pdf.xyz.