PDF to JPG: what the DPI setting does to your pages
To turn PDF pages into JPG images, pick a resolution in DPI, choose the pages, and convert. DPI, dots per inch, sets how many pixels each inch of the page becomes. At 150 DPI an A4 page becomes a 1240 × 1754 pixel image, which suits screens and email. At 300 DPI it becomes 2480 × 3508, which suits printing. The tool below draws each page in your browser, so the PDF is never uploaded.
PDF to JPGNeed the pages as picturesOpenWhat DPI does
A PDF describes a page in physical units, not pixels. An A4 page is 210 by 297 millimetres, which is 8.27 by 11.69 inches. A US Letter page is 8.5 by 11 inches. To make a picture from a page, the tool needs a pixel count, and DPI sets it. Pixels on each side equal the page's inches multiplied by the DPI.
Doubling the DPI doubles each side of the image, and that quadruples the number of pixels. An A4 page at 150 DPI has 1240 × 1754, about 2.2 million pixels. At 300 DPI it has 2480 × 3508, about 8.7 million. The 300 DPI image is four times as large in pixels, not twice.
These are the sizes for the three settings:
| Page | 72 DPI | 150 DPI | 300 DPI |
|---|---|---|---|
| A4, 8.27 × 11.69 in | 595 × 842 | 1240 × 1754 | 2480 × 3508 |
| US Letter, 8.5 × 11 in | 612 × 792 | 1275 × 1650 | 2550 × 3300 |
Each figure is rounded to the nearest whole pixel, so the tool may differ by one pixel from the table.
Very large pages have a limit. The tool keeps the longest side at 8,000 pixels or less, and the total at about 40 megapixels, to protect a phone's memory. A poster in A0 size, 841 by 1189 millimetres, would be about 9,930 by 14,040 pixels at 300 DPI. The tool scales that page down and shows a note.
Choosing a resolution
- 72 DPI gives the smallest files. It suits thumbnails and quick previews, but small text on it looks soft.
- 150 DPI is sharp on a screen at full size and works well for email, chat and most web uses.
- 300 DPI is the usual choice for printing. A 150 DPI image printed at A4 size puts 150 dots on each inch of paper, so small text can look soft on paper.
Pick the lowest setting that keeps the text clear at the size you will show it.
JPG or PNG for text pages
JPG is a lossy format. It discards some detail to keep the file small, and the discarded detail is most visible around sharp edges. Black letters on white paper have many sharp edges, so a low JPG quality leaves faint halos and speckles around the text. For text-heavy pages, raise the JPG quality slider, or choose PNG.
PNG is lossless. Every pixel is stored exactly, so text stays crisp. The cost is size. A page with photographs makes a large PNG, while a page of plain text is usually small.
A scanned PDF page is already an image inside the PDF. Converting it with a lossy format adds another round of compression, so use PNG or a high JPG quality for scans.
Converting to images has one cost you should plan for. The output pages are pictures, so their text cannot be searched or copied. Keep the PDF if you still need the text.
Page ranges
Leave the page field alone to convert every page. To convert some pages, type ranges and single pages separated by commas, such as 1-3, 5. Each page is saved as its own image, and you can download them one at a time or all together as a ZIP.
Use a range when you only need a few pages from a long report, such as the charts or a signature page. A range saves time and avoids a folder of images you will delete later.
Password-protected PDFs
A PDF with an open password cannot be rendered until the password is removed. Unlock it first, using the password you have, in the program you normally use for that document. Then convert the unlocked copy. The tool does not try to get past a password.
When to split the PDF instead
Converting to images is not always the right step. Consider splitting first when:
- You need some pages as PDF files, not pictures. Split the PDF extracts the pages you choose, or saves every page as its own file. The pages stay PDF, so their text stays searchable.
- You only need one page as an image. Convert just that page with a page range, rather than every page and then picking out one.
- You want to combine the images again. Images to PDF does the reverse: it combines JPG, PNG and WebP photos into one PDF, in the order you choose.
A common path is to split a long PDF into the sections you need, convert only the sections that must be images, and merge the PDF sections back together with merge PDF.
Quick answers
Which DPI should I choose? 150 DPI for screens, email and chat. 300 DPI for printing. 72 DPI only when file size matters more than sharpness.
Why is my JPG blurry? Usually the JPG quality is low for a page full of text. Raise the quality slider, or use PNG for text-only pages, then check the result at 100 percent zoom.
Are the pages uploaded? No. A PDF library in your browser draws each page on your device, and your original file is not changed.
Why is a page smaller than the setting I chose? Very large pages are capped to protect memory. A note appears when a page is scaled down.
