How to convert a PDF to JPG on iPhone
iOS has no built-in way to save PDF pages as image files, and screenshotting captures your screen rather than the page - so text goes soft and the interface comes along for the ride. To get real images you render the PDF at a chosen resolution: pick the pages, choose JPG or PNG and 150 or 300 DPI, then save or export them as a ZIP.
The short answer
iOS has no built-in command that turns a PDF into image files. The two workarounds people reach for - screenshotting each page, or taking a screenshot in Books - both capture your screen rather than the page, so you get whatever resolution your display happens to be, plus the interface around it.
To get the actual page as an image, you need something that renders the PDF at a chosen resolution. That is a one-tap job in a converter app, and the only reliable way to do it on a phone.
Why screenshots are not good enough
A screenshot is a picture of your screen. A PDF page is a set of drawing instructions that can be rendered at any size. Screenshotting throws that away and keeps whatever was on screen at the moment - typically far less detail than the page contains.
In practice that means:
- Text goes soft as soon as anyone zooms in or prints it.
- You capture the app around the page - toolbars, page counters, the edges of the next page - and have to crop each one by hand.
- It does not scale. Forty pages means forty screenshots, forty crops, and a camera roll you then have to sort through.
- The aspect ratio is wrong. You get your screen's shape, not A4's.
How to convert a PDF to JPG on iPhone
Using JPG To PDF Converter PRO:
- Tap PDF to JPG on the home screen and pick the PDF - from Files, iCloud Drive, or anywhere the iOS file picker can reach.
- The document opens as a grid of pages. Tap Select All for the whole document, or tick just the pages you need.
- Choose the output format - JPG for photographs and general use, PNG for diagrams, screenshots and anything with sharp edges or flat colour.
- Choose the resolution: 150 DPI for on-screen use, 300 DPI when the image will be printed or zoomed into.
- Save the images to Photos, share them, or export the whole set as a single ZIP.
JPG or PNG?
They are not interchangeable, and picking wrong is the most common cause of "why does this look bad".
- JPG compresses by discarding detail the eye is unlikely to notice. Excellent for photographs and scanned pages; files are small. On sharp black text against white, heavy compression leaves faint grey smudging around the letters.
- PNG is lossless - every pixel survives exactly. Better for line drawings, charts, logos and text-heavy pages. Files are substantially larger.
Rule of thumb: if the page is mostly a photograph, use JPG. If it is mostly lines and letters and the image will be looked at closely, use PNG.
Which DPI do you actually need?
DPI decides how many pixels the page is rendered into. An A4 page at 150 DPI is roughly 1240 × 1754 pixels; at 300 DPI it is about 2480 × 3508.
- 150 DPI - sending in a chat, dropping into a slide, posting online, attaching to an e-mail. Sharp on any screen, small enough to send without thinking about it.
- 300 DPI - printing, zooming in on fine print, archiving, or anything that will be cropped afterwards. Roughly four times the pixels and four times the file size.
Going higher than you need costs storage and upload time and gains nothing visible on a screen.
Exporting a whole document
Once a document runs past a handful of pages, saving images one at a time stops being sensible - and forty loose images in a chat is nobody's idea of a document. Exporting the set as a ZIP keeps them together, in order, as one attachment the person at the other end can unzip in one move.
Tips
- Only convert the pages you need. The page picker exists so you do not render forty pages to get page twelve.
- Saving to Photos makes images searchable. iOS reads text in images, so a page saved to Photos can be found later by searching a word on it.
- PNG for anything going into a slide deck. Slides get projected and zoomed, which is exactly where JPG artefacts show up.
- Check page one before converting the rest. Convert a single page first and look at it; if the settings are wrong you have wasted one page, not forty.
Common mistakes
- Screenshotting a page that needs to be printed. Screen resolution is roughly a third of print resolution. It will look soft on paper.
- Using 300 DPI for a chat message. A large file that takes longer to send and looks identical on the recipient's phone.
- JPG for a page of small text. Compression artefacts cluster around sharp edges, which is precisely what letters are made of.
- Sending forty separate images. Export the ZIP.
- E-mailing the PDF to yourself to do it on a laptop. That is a copy of your document sitting in two mailboxes on somebody's mail server, for a job the phone can do offline.