Format Guide
PDF vs PNG: What is the difference and when to use each?
PDF and PNG serve fundamentally different purposes. PDF is a document format designed for sharing and printing multi-page content. PNG is an image format designed for lossless, pixel-perfect graphics. Understanding the difference helps you choose the right format for your workflow and know when converting between them makes sense.
Quick comparison
| Feature | PNG | |
|---|---|---|
| Format type | Document format | Image format |
| Content | Text, images, vectors, forms | Pixels (raster image) |
| Pages | Multiple pages per file | Single image per file |
| Text selectability | Yes (text is selectable) | No (text is pixels) |
| File size | Varies (often compact) | Larger per page |
| Editing | Requires PDF editor | Any image editor |
| Transparency | Limited | Full alpha channel |
| Best for sharing | Documents and forms | Images and social media |
What is PDF?
PDF (Portable Document Format) was created by Adobe to present documents consistently across devices and operating systems. A PDF can contain text, images, vector graphics, interactive forms, annotations, and embedded fonts. It supports multiple pages in a single file and preserves the exact layout intended by the author.
PDF is the standard format for contracts, invoices, reports, manuals, and any document that needs to look the same on every device. Text in a PDF is selectable and searchable, which makes PDFs useful for archiving and document management.
However, PDFs are not ideal for every situation. Many social media platforms, image galleries, and content management systems do not accept PDF uploads. Some email clients display PDFs inconsistently. And editing a PDF requires specialized software.
What is PNG?
PNG (Portable Network Graphics) is a raster image format that uses lossless compression. Every pixel in a PNG is preserved exactly as stored, making it ideal for images where sharpness and accuracy matter. PNG also supports an alpha channel for full or partial transparency.
PNG files contain a single image. If you have a 10-page PDF and convert it to PNG, you get 10 separate PNG files, one for each page. Each PNG can be opened in any image viewer, uploaded to any platform that accepts images, and edited in any image editor.
The trade-off is that PNG files can be large, especially at high resolutions. A single letter-size page at 300 DPI can produce a PNG file of 1-3 MB. For multi-page documents, this adds up quickly.
When to keep your file as PDF
- Sending contracts, invoices, or legal documents that need to look identical everywhere
- Archiving documents with selectable and searchable text
- Sharing forms that recipients need to fill out digitally
- Printing multi-page documents at a print shop or office printer
- Any situation where the recipient needs to search, select, or copy text
When to convert PDF to PNG
- Sharing document pages on social media (Instagram, Twitter, LinkedIn, Facebook)
- Uploading pages to a website, blog, or CMS that only accepts image files
- Embedding document pages in presentations (PowerPoint, Keynote, Google Slides)
- Sending pages as email attachments where the recipient may not have a PDF viewer
- Creating image previews or thumbnails for a document gallery
- Extracting charts, diagrams, or graphics from a PDF for reuse
How to convert PDF to PNG
The most common way to convert PDF to PNG is using an online converter. However, most online tools require you to upload your PDF to a remote server, which is a privacy concern for sensitive documents like contracts, invoices, and medical records.
RasterMint offers a browser-based alternative. It renders each PDF page locally using PDF.js (by Mozilla) and exports the result as a PNG image. Your file never leaves your device. You can choose between 72 DPI for quick previews, 150 DPI for general sharing, and 300 DPI for print-quality output.
Desktop alternatives include macOS Preview (File → Export → PNG for one page at a time) and Adobe Acrobat (full export features but requires a paid license). On Windows, there is no built-in PDF to PNG converter, so a browser-based tool like RasterMint is often the most convenient option.
DPI settings for PDF to PNG conversion
DPI (dots per inch) controls the resolution of the output PNG. Higher DPI means more pixels and sharper output, but also larger file sizes.
- 72 DPI — Small file, screen-resolution. Good for quick previews.
- 150 DPI — Best balance of quality and size. Recommended for most use cases.
- 300 DPI — Print-quality. Use when the PNG will be printed or archived.