How to convert a PDF to images
- Drop a PDF onto the box or press Choose files. If the file has an open password, a password box appears; the password is used only inside this page to decrypt the file.
- Pick PNG or JPG, and a resolution: 72 DPI for quick previews, 150 DPI for images that look sharp on modern screens, 300 DPI for printing.
- Leave Pages empty to convert everything, or list pages such as 1-3, 5.
- Press Convert to images. Each page appears as it is finished, with its pixel size and file size. Download pages one at a time, or press Download all (ZIP).
Pages are rendered one after another and appear as they finish, so you can stop a long document part-way and keep what has already been converted.
How pages become images
A PDF page is a list of drawing instructions — place this glyph from this font here, fill this path, draw this image there — measured in points, where one point is 1/72 of an inch. To make an image, the page is drawn onto a grid of pixels with pdf.js, the PDF renderer built into Firefox, and the grid is then encoded as PNG or JPG.
What DPI means here
DPI (dots per inch) sets how many pixels represent one inch of the page. The pixel size is the page size in inches multiplied by the DPI. An A4 page is 595 × 842 points, or 8.27 × 11.69 inches, so at 150 DPI it becomes 1,240 × 1,754 pixels and at 300 DPI 2,480 × 3,508 pixels. At 72 DPI one point becomes one pixel, so a US Letter page (612 × 792 points) becomes exactly 612 × 792 pixels.
PNG or JPG
PNG is lossless: text and line art stay perfectly crisp, which makes it the better choice for documents, slides and diagrams. JPG discards detail the eye is less sensitive to, which makes photographs and scans much smaller but can leave faint smudges around sharp text. For a page of text, PNG at 150 DPI is usually both clearer and not much larger. Both formats are drawn on a white background, as a PDF reader shows the page.
Very large pages
Browsers limit how big a single drawing surface can be; Safari's limit is about 16.7 million pixels. To make sure every browser can render the page, the tool lowers the resolution for a page that would exceed 16 million pixels and tells you when it has done so. A3 at 300 DPI is rendered at 287 DPI (3,356 × 4,746 pixels); an A0 poster at 101 DPI.
Examples
| Page | Resolution | Image size |
|---|---|---|
| A4 (595 × 842 pt) | 150 DPI | 1,240 × 1,754 px |
| A4 | 300 DPI | 2,480 × 3,508 px |
| US Letter (612 × 792 pt) | 72 DPI | 612 × 792 px |
| A3 (842 × 1,191 pt) | 300 DPI requested | 287 DPI used: 3,356 × 4,746 px |
| A0 (2,384 × 3,370 pt) | 300 DPI requested | 101 DPI used: 3,344 × 4,728 px |
Typical uses: a single slide from a PDF deck for a chat message (PNG, 150 DPI, one page); a form that must be uploaded as an image (JPG, 150 DPI); a page for a printed flyer (PNG, 300 DPI).
Limits
- The image is not searchable. Text in the image is just pixels; to keep selectable text, share the PDF itself or split out the page you need with the Split PDF tool.
- Fonts that are not embedded in the PDF are replaced by a similar standard font, as they are in any viewer, so the image can look slightly different from the author's screen.
- Very large pages are rendered at a lower resolution, as described above.
- Memory. Hundreds of pages at 300 DPI produce gigabytes of pixels. Convert long documents in batches, or use 150 DPI, if your device struggles.
- Colour profiles and overprint. Print-oriented features such as spot colours and overprint are approximated for screen display; a professional RIP may produce slightly different colours.
Frequently asked questions
Is my PDF uploaded to a server?
No. Pages are rendered by pdf.js inside your browser, and the images are created on your device.
What resolution should I choose?
150 DPI for anything viewed on a screen, 300 DPI for printing, 72 DPI for small previews. Higher resolutions make larger files.
Should I pick PNG or JPG?
PNG for pages that are mostly text, lines or flat colour; JPG for scanned photos or when file size matters more than perfectly sharp edges.
Can I convert a password-protected PDF?
Yes, if you know the password. Enter it when asked; it is used only inside this page to open the file and is never sent anywhere.
Why is my image smaller than I asked for?
For pages larger than about A3, the resolution is lowered so the image stays under 16 million pixels, the most every browser can reliably draw. The status line says when this happens.