PDF to Images

about this tool

Pages to pixels

Drop a PDF, choose a format and a dpi, and the panel shows the pixel size each page will have: PDF pages are measured in points, 72 to the inch, so an A4 page at 150 dpi is 1240 × 1754 pixels. The pages box takes the same range grammar as the other PDF tools — 1-3, 5, odd, last — and defaults to all. Repeated pages are rendered once, since each image gets its own file name. Convert draws the pages one after another and lists them as they finish, with a download button each; Download saves a single image directly or zips several in the browser.

Formats

PNG is lossless and keeps text edges crisp. JPEG is smaller and soft on text; it has no alpha channel, so its background is always white. WebP is offered when the browser can encode it and is smaller than JPEG at the same quality, with transparency. The three quality presets apply to JPEG and WebP. With PNG or WebP you can leave the background unpainted, so a page that draws no background of its own comes out as content on transparency.

How it renders

pdf.js loads on first use, with its worker and image decoders served from this site, and draws each page onto a canvas at the planned size; the browser's own encoder writes the image. Browsers cap what a canvas can hold — 16,384 pixels a side in Chrome, about 16.8 million pixels in total on iOS — so the plan caps the dpi of pages that would exceed the known limit and says so, and if the browser still refuses a canvas the page is retried at half the dpi, up to three times. The dpi actually used is shown under each image when it differs from the request.

Nothing leaves the page

Rendering, encoding and zipping all happen in your browser. There is no upload and no size limit beyond your device's memory; the panel warns when the planned images add up to more than about 150 megapixels, which can be too much for a phone. Encrypted PDFs are refused with the reason, since they cannot be drawn without the password.

Limits

Output quality is whatever the browser's encoder produces: no dithering choices, no colour profile, no metadata — the images carry no dpi tag, so an editor may assume 72 or 96 when you open them. Annotations render as a viewer would show them; form field values are drawn, but nothing is editable. Nothing is stored between visits.

The reverse trip is images to PDF. If the pages came out larger than you wanted, image compressor will bring the files down.

questions

Which dpi should I pick?

72 dpi matches a screen at 100 percent: an A4 page becomes 595 × 842 pixels. 150 dpi is good for slides and documents, 300 dpi for print. The pixel size for your pages updates as you change it, and a custom value from 18 to 1200 is accepted.

PNG, JPEG or WebP?

PNG is lossless and keeps text crisp, at the cost of size. JPEG is much smaller but softens edges and cannot be transparent. WebP is smaller than JPEG at the same quality and supports transparency; it is offered when your browser can encode it.

Can I get a transparent background?

Yes, for PNG and WebP: tick the option and the page background is left unpainted, so only the drawn content shows. Most PDFs draw no background of their own, so the result is the page content on transparency. JPEG has no alpha channel and always gets white.

Is anything uploaded?

No. pdf.js draws each page onto a canvas in your browser and the browser encodes the image; several images are zipped in the browser too. Nothing leaves the page and nothing is stored between visits.

Why did a page come out at a lower dpi than I asked?

Browsers cap canvas size — Chrome at 16,384 pixels a side, Safari on iOS at about 16.8 million pixels in total. Pages that would exceed the known cap are planned at the largest dpi that fits, and if the browser still refuses, the page is retried at half the dpi. The image list shows the dpi actually used.