PDF to JPG

Choosing a resolution

A PDF page has a physical size, such as 8.5 × 11 inches, but an image is measured in pixels. The resolution, in dots (pixels) per inch, decides how many pixels each inch of the page gets. These are the sizes the tool makes:

150 dpi is the everyday choice: an image about as wide as a laptop screen, small enough to email, and sharp enough to read. 300 dpi is the usual resolution for printing, and it lets people zoom in on fine print, signatures or small table figures. Doubling the dpi makes four times as many pixels, and files typically two to four times larger. 72 dpi suits thumbnails and quick previews.

A scanned PDF has its own resolution, set when it was scanned. Converting a 200 dpi scan at 300 dpi adds pixels but no detail, so 150 dpi is usually enough; choose 300 only if the scan was made at 300 dpi or more.

What the images keep

Each image is a picture of the page exactly as it looks in a PDF reader: text, photos, stamps, signatures and filled-in form fields. Because it is a picture, the text is no longer selectable or searchable and links stop working. If you need the words themselves, use PDF to text instead.

JPG or PNG?

JPG makes small files and handles photos well, which is why it is the default here. It does soften the edges of letters a little, more so at lower quality. PNG is lossless: every pixel is kept exactly, which suits text-heavy pages, charts and diagrams, and it can make the background transparent. See PDF to PNG for more on when it is the better choice.

The JPG quality setting decides how hard each image is compressed. 90% is the default because letters stay clean at that level. Lower settings make smaller files, which helps when a website or form limits upload size, but small text starts to look smudged. Previews show each image’s size, so you can compare before you download.

Long documents and big pages

• Page by page: pages are drawn one at a time with a progress bar, and you can cancel and keep the images already made.
• Very large pages such as posters and engineering drawings can exceed what a browser can draw at 300 dpi. They are made at the highest resolution that fits, and the tool tells you which dpi was used.
• Huge sets of images are split into ZIP parts of about 500 MB, so the download doesn’t run out of memory.

To convert only a section of a long report, you can also extract those pages first, and if pages are sideways, rotate the PDF before converting. Going the other way, image to PDF turns photos and scans back into a single PDF.