PDF-to-image resolution and quality explained

Resolution controls pixel dimensions

At 1×, a PDF point maps roughly to one CSS pixel in the renderer. A standard A4 page is about 595 × 842 pixels. At 2× it becomes about 1190 × 1684—four times as many pixels, not twice the memory.

Use PNG for line art and JPG for photographs

PNG is lossless and usually sharper for text, diagrams and screenshots. JPG is smaller for photographic pages but introduces compression artefacts around thin lines.

For a presentation chart, use PNG at 2×. For a scanned photo archive, JPG around 85–90% quality is a reasonable starting point.

Export only the pages you need

Rendering 100 pages at 3× can consume substantial memory. Select a smaller page range or reduce resolution if the browser reports its safe pixel limit.

Know what becomes unavailable

An image has no searchable PDF text, links, form controls or scalable vector instructions. PDF-to-image is not OCR and does not extract original embedded images.