Converting PDF pages to images — which DPI, JPG or PNG?
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To put a PDF page in a slide deck, send it in a chat or post it on a website, you need it as an image. The DPI and format you choose decide how sharp and how large the result is.
What DPI means
DPI (dots per inch) is how many pixels are used for each inch of the page. A PDF page has a real physical size, so choosing a DPI fixes the image’s pixel dimensions.
Formula: image width in pixels = page width in inches × DPI
For a US Letter page (8.5 × 11 inches):
| DPI | Image size of one page | Good for |
|---|---|---|
| 72 | 612 × 792 pixels | Thumbnails and previews |
| 150 | 1275 × 1650 pixels | Screens, slides, sharing in chats |
| 300 | 2550 × 3300 pixels | Printing, zooming into fine detail |
Doubling the DPI quadruples the number of pixels — and roughly the file size and processing time.
What to choose
- Slides or documents: 150 DPI is plenty; screens rarely show more detail than that.
- Email and messaging: 150 DPI — text stays readable when zoomed on a phone.
- Printing: 300 DPI. Print is much denser than a screen, and lower resolutions look soft on paper.
- Website thumbnails: 72 DPI — small and light.
The PDF to JPG and PDF to PNG converters default to 150 DPI.
JPG or PNG?
| JPG | PNG | |
|---|---|---|
| Compression | Lossy (discards detail the eye barely notices) | Lossless (every pixel kept) |
| File size | Small | Large |
| Pages full of photos | ✅ Ideal | Large files |
| Text, tables, diagrams | Faint blotches around letters | ✅ Crisp |
| Transparency | No | Yes |
In short: JPG for photo-heavy pages, PNG for text, tables and slides. Both converters render pages on a white background, exactly as your PDF viewer shows them.
Convert only the pages you need
Rendering a 100-page PDF at 300 DPI takes time and space. Type the pages you want into the Pages field — for example 1, 5-7 — and only those are converted. Several images are delivered as one ZIP file.
Phones have limited memory, so converting a large PDF at high resolution in one go can be slow; splitting it into page ranges helps.
And back again
To bundle images into a PDF, use JPG to PDF — see How to combine phone photos into one PDF.
Summary
Choose 150 DPI for screens, 300 DPI for print and 72 DPI for thumbnails. Use JPG for photos and PNG for text and diagrams, and convert only the pages you need.