Turning a PDF page into an image is simple enough — the format you export to is the part people skip past, and it's the part that decides whether the result looks sharp or file sizes get out of hand.
JPG: smaller files, lossy compression
JPG compresses by approximating the image, throwing away detail a viewer is unlikely to notice. That makes it a good default for pages with photos, gradients, or scanned content — file sizes stay small, and the quality loss is barely visible at normal zoom. The tradeoff shows up on pages with sharp text or fine lines: JPG compression can introduce a faint blur or blocky artifacts around high-contrast edges, which is more noticeable on a page of text than a photo.
PNG: larger files, lossless quality
PNG doesn't throw anything away — every pixel is preserved exactly. That makes it the better choice for pages that are mostly text, diagrams, tables, or anything with hard edges and flat colors, where you want crisp lines rather than smoothed-over detail. The cost is file size: a lossless format simply can't compress as aggressively as one that's allowed to approximate, so PNG exports of the same page usually end up notably larger than JPG.
A simple rule of thumb
If the page is mostly a photo or scanned image, export to JPG. If the page is mostly text, diagrams, or anything you might zoom into, export to PNG. If you're not sure and file size isn't a concern, PNG is the safer default — you can always compress it down afterward, but you can't recover detail a lossy format already discarded.
Both conversions run entirely in your browser using pdf.js to render each page and export it directly — no upload required either way.
What resolution to export at
Format aside, the resolution you render at matters just as much. A page rendered at 72–96 DPI looks fine on a screen but turns visibly soft the moment you zoom in or print it. Rendering at 150 DPI is a solid middle ground for documents that might be printed at some point, and 300 DPI is the standard for anything going to a professional printer or that needs to preserve fine detail — small print, technical diagrams, anything with text you might need to read at actual size later. Higher resolution means a larger file regardless of format, so there's no reason to render at 300 DPI for something that will only ever be viewed in a chat window.
What about WebP or other newer formats?
WebP offers both lossy and lossless modes in one format, generally beating JPG and PNG on file size at equivalent quality. Its main limitation is compatibility — older software and some document-management systems still don't handle it cleanly, which is exactly the kind of friction you don't want when you're converting a page specifically to share it somewhere. JPG and PNG remain the safer default precisely because virtually everything opens them without a second thought; WebP is worth considering only when you control both ends of the exchange and know the recipient's software supports it.
Converting more than one page at once
If you're exporting a multi-page document, decide upfront whether you need every page as a separate image file or just one or two specific pages. Exporting the whole document produces one image per page, which is useful for feeding into a slideshow or an image gallery, but overkill if you actually only needed the cover page as a thumbnail. Extracting the specific page you want first, then converting just that one page, keeps the output focused and avoids ending up with a folder full of images you don't need.
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