PDF to Long Image

A long image is every page of a PDF stacked into one tall picture. It is the easiest way to show a document where PDFs are awkward: a blog post, a chat message, a shop's product detail page or a social post that only takes images. This tool renders each page at the width you choose, stacks them with an optional gap and saves one JPG or PNG. Your files never leave your device.

How to use this tool

1. Choose one or more PDF files — each becomes its own long image.
2. Pick the width: 860 px suits Korean shopping detail pages, 1080 px is a good general size, 1440 px keeps small text sharp.
3. Optionally choose pages, a gap and its colour (use #ffffff and 0 px for a seamless page).
4. Pick JPG for small files or PNG for crisp text, then download the image (or several, if the document is very long).

Formula

Each page is drawn at scale = width ÷ page width, so its height is page height × scale. Heights and gaps are added until the next page would pass the height limit; then a new image starts.

Browsers cap canvas size: iPhone and iPad Safari about 16.7 million pixels per image, Chrome, Edge and Firefox 32,767 px per side. The safe setting keeps every image under both limits.

Example

An A4 page is 595 × 842 pt. At 1080 px wide the scale is 1080 ÷ 595 ≈ 1.815, so each page is about 1528 px tall. Ten pages with a 12 px gap give 10 × 1528 + 9 × 12 = 15,388 px: one image, just under the safe limit at this width (16,777,216 ÷ 1080 ≈ 15,534 px). A 20-page file at the same width is split into two images of 10 pages.