PNG is the format for sharp-edged images: screenshots, charts, diagrams, logos and interface mockups. Those images suffer badly under JPEG compression, which blurs small text and adds speckles around lines. PNG to PDF keeps them lossless, so a screenshot of a spreadsheet or a technical diagram is as crisp in the PDF as it was on your screen.
How to use PNG to PDF
- Add one or more PNG files.
- Drag them into page order.
- Select Convert to PDF.
- Download the PDF, with one image on each page.
Lossless in, lossless out
- Every pixel is kept: A PNG stores every pixel exactly, and VelloDoc keeps it that way. It adds PNG images with lossless compression instead of turning them into JPEGs, which would blur small text and leave halos around lines.
- The trade-off is size: a large screenshot stored losslessly takes more space than a JPEG of the same picture.
- For photographs instead: For documents dominated by photographs instead of sharp graphics, JPG to PDF or a pass through Compress PDF will give a smaller file.
What happens to transparency
- Transparent areas are common: PNGs often contain transparent areas, like a logo with no background or a screenshot with rounded corners.
- Placed on white: Pages created by this tool have a white background, so transparent pixels are placed on white before the page is built. That avoids the common conversion problem where transparent regions turn solid black.
- For a colored background: If you want a colored background instead, add it to the image before converting.
Screenshots as documentation
- A series of screenshots: Step-by-step guides, bug reports and training materials are often a series of screenshots. Converting them into one PDF keeps them in order and makes them easy to print or attach.
- Number the pages with Add Page Numbers so readers can refer to each step, and because screenshot text is part of the image, run OCR PDF if the words need to be searchable.
- Where to read more: The format guide compares PNG, JPG and PDF.
When people use PNG to PDF
Bug reports and tutorials
Bundle a sequence of screenshots into one ordered document that developers or trainees can follow step by step.
Charts and diagrams
Share exported charts and technical diagrams as a PDF without the blur that JPEG adds to lines and labels.
Design mockups for review
Send interface mockups to a client as a single file that preserves crisp edges and exact colors.
Limitations to know
PNG to PDF keeps images lossless. This makes files larger than JPEG-based conversions of photos. Transparency is placed on white, pages are sized from pixel dimensions, and text inside screenshots isn't searchable until OCR is applied.
PNG to PDF: common questions
Will transparent backgrounds turn black?
No. Transparent areas are composited onto white before each page is created, so logos and cut-out images appear on a clean white page.
Why is my PDF larger than I expected?
Lossless storage keeps every pixel, which takes more space than lossy JPEG. If a smaller file matters more than pixel-perfect sharpness, compress the PDF afterwards.
What happens with animated PNGs?
Animated PNGs are split into their frames, with one page per frame. If you only want one frame, export it as a still image before converting.
What page size will the PDF use?
Each page matches its image at 150 pixels per inch, so a 1,500-pixel-wide screenshot becomes a 10-inch-wide page. Viewers fit it to the window, and printers scale it to the paper.