Converting a PDF to JPG: Which Resolution to Pick
· 5 min read
Pick the DPI by what the image is for: 72 to 96 for screens and email, 150 for a readable reference copy, 300 when the text must stay legible at full size or be printed. Higher is not better — it multiplies the file size without adding detail the original page never had.
Converting a PDF page into a picture involves one real decision and a lot of noise around it. The decision is resolution, and getting it wrong in either direction is the reason people end up with a blurry screenshot or a forty-megabyte image of a single page.
On this page
What DPI actually controls
A PDF page has no pixels. It is a description — put this glyph here, draw this line there — which a viewer renders at whatever size you ask for. DPI is you telling it how large to render.
At 72 DPI an A4 page becomes roughly 595 by 842 pixels, which is about what it occupies on screen. At 300 DPI the same page is around 2480 by 3508, which is print resolution. Nothing is gained or lost in the page itself; you are choosing how finely to sample it.
| DPI | A4 becomes | Good for |
|---|---|---|
| 72–96 | ~600 × 850 | Screens, email, a quick preview |
| 150 | ~1240 × 1750 | A readable reference copy |
| 300 | ~2480 × 3500 | Printing, or text legible at full size |
| 600 | ~4960 × 7000 | Archival, and rarely justified |
Why higher is not better
Doubling the DPI quadruples the pixel count, and file size follows. A 600 DPI page image can be tens of megabytes, which is unusable for the thing most people are doing — attaching it to an email or putting it in a document.
It also does not always add detail. If the page contains a photograph embedded at low resolution, rendering the page at 600 DPI gives you a very large picture of a blurry photograph. The upper bound on quality is whatever the original page contained, not what you ask the renderer for.
PDF to ImageExport chosen pages as PNG or JPG at any resolutionJPG or PNG
For a page that is mostly photographic, JPEG is right and much smaller. For a page that is mostly text, diagrams or flat colour, PNG is usually both sharper and smaller, because lossless compression handles large areas of one colour extremely well while JPEG puts visible artefacts around every letter.
The instinct to pick JPEG for everything comes from photography, where it is correct. On a page of text at moderate resolution it is the wrong choice, and the fuzziness people blame on the DPI is often the compression instead.
- Scanned photographs and image-heavy pages: JPEG
- Text, tables, line drawings, screenshots: PNG
- Anything going to print: PNG at 300 DPI
- Anything being emailed: JPEG at 96 to 150
When you want extraction instead
This is the mix-up worth avoiding, because it costs quality silently. Converting a page renders everything on it — text, background, and the photograph — into one flat picture. If what you actually wanted was the photograph, you have taken a screenshot of it rather than a copy.
The picture embedded in a PDF is frequently higher resolution than the page it appears on, because it was placed and scaled down. Extracting it returns the original file; rendering the page returns a downscaled version with the surrounding text baked in.
So: use page conversion when you want the page. Use image extraction when you want something that is on it.
A page count worth checking first
Rendering is the most computationally expensive thing most PDF tools do, and it scales with both page count and DPI. A three-hundred page document at 300 DPI is a large amount of work and a very large amount of output.
Convert the pages you need rather than the whole document. Most tools take a page range, and it is the difference between a few seconds and a phone running out of memory.
Doing it without uploading the document
Rendering a PDF page needs a renderer, and browsers have had a capable one for years. There is no requirement for the document to be sent anywhere for this.
It matters here because rendering is what people reach for with documents they are about to share — a page of a contract, a certificate, a statement. A browser-based tool reads the file from your device and produces the images locally, which you can verify in the Network tab or by disconnecting once the page has loaded.
Common questions
What DPI should I use to convert a PDF to JPG?
72 to 96 for screens and email, 150 for a readable reference copy, 300 for printing or when text must stay legible at full size. Going higher multiplies the file size without adding detail the page never contained.
Why is my converted image blurry?
Usually the DPI was too low — try 150 or 300. If raising it does not help, the page itself contains a low-resolution image, and no amount of rendering will add detail that was never there.
Should I choose JPG or PNG?
JPEG for photographic pages, PNG for text, tables and line drawings. JPEG puts visible artefacts around lettering, so a page of text at moderate DPI often looks worse and takes more space as a JPEG than a PNG.
Why is my converted file so large?
Doubling DPI quadruples the pixel count. A single page at 600 DPI can be tens of megabytes. Drop to 150 unless it is going to print.
How do I get the photo out of a PDF rather than the page?
Use image extraction, not page conversion. The embedded picture is often higher resolution than the page shows, so rendering the page gives you a downscaled copy with the surrounding text baked in.
Does converting keep the text selectable?
No, and it cannot. An image has no text — every character becomes pixels. If you need the text, keep the PDF or run the images through OCR afterwards.
Can I convert only some pages?
Yes, and you should for anything long. Rendering scales with page count and DPI together, so converting three hundred pages at 300 DPI is where phones run out of memory.
Is my PDF uploaded to convert it?
It does not need to be. Browsers have had a capable PDF renderer for years, so the whole conversion can happen on your own device with nothing transmitted.