Which resolution should a PDF page have as a JPG? For most uses, the default 150 DPI. A Letter page comes out 1275 × 1650 pixels, enough to read a statement comfortably on a phone or a laptop, and a page of text stays well under 100 KB.
Pixels and file sizes, page by page
We converted all three pages of a Letter-size sample at each setting: a statement with a small table, a page that is one large photo, and a short list.
| Setting | Pixels per page | Statement | Photo page | List |
|---|---|---|---|---|
| Screen, 72 DPI | 612 × 792 | 25.5 KB | 59.1 KB | 9.1 KB |
| Standard, 150 DPI | 1275 × 1650 | 68.4 KB | 206 KB | 28.0 KB |
| Print, 300 DPI | 2550 × 3300 | 185 KB | 639 KB | 83.3 KB |
Standard took under a second per page; Print took 2 to 2.6 seconds per page, so a long document at 300 DPI is worth a short wait.
Matching the setting to the job
- Screen suits a thumbnail or a quick look in a chat. At 72 DPI one pixel stands for one point, so 9-point print is only about 9 pixels tall and small text gets hard to read.
- Standard is right for a website that only accepts images, a page in a slide, or a ticket you want on your phone.
- Print is for printing at full size or reading fine print up close. We would not pick it for email: the photo page alone was 639 KB, three times its Standard size.
If your pages are mostly text, tables or line drawings and you want perfectly clean edges, switch “Convert to” to PNG or use PDF to PNG; the files get larger. To go the other way, JPG to PDF puts images back into one PDF.
Very large pages
Each page is drawn on a white background at the chosen DPI and saved as JPG at quality 90, higher than usual for photos, so letters keep clean edges. Some phone browsers refuse images much over 16 million pixels, so every page is capped there. An A3 page at 300 DPI would be about 17.4 million pixels; it is drawn at about 288 DPI instead, roughly 3360 × 4760 pixels. Each result shows its real pixel size, so you can see when this happened.