Why is my PDF poor quality?

Good quality documents are important, especially in the professional world. A poorly formatted document can cause miscommunication between workplaces and make it difficult for your clients to understand what you’re trying to say. A PDF is a great way to ensure that your documents will always look their best! However, sometimes a PDF can be of poor quality for many reasons—it might be too big or have too many fonts or images, or simply not have enough resolution. So how do you know if your PDF is ready to print? Let’s take a look at some of the most common culprits for poor quality so that you know exactly what makes an image bad!

File size

  • If the file size is too large, it will take a long time to download.
  • If the file size is too small, it may not be of good quality.
  • Consider reducing the number of pages or images in your document if you want to reduce its file size.

Image size

  • Too small. Clear images are vital to the readability of your PDF, so make sure you have the right size. Ideally, it should be at least 500 pixels wide by 700 pixels tall.

If you’re working from a digital camera or smartphone (and not from a scanner), adjust the image size before uploading to make sure that it’s big enough.

  • Too large. There’s some disagreement about how big an image should be for a PDF file—it depends on how large or small your page is and whether you plan on printing it out—but we suggest keeping them under 1 MB each in order to avoid unnecessary file size issues and slow loading times.


The resolution of your PDF is measured in dots per inch (dpi). This is not a measure of quality, but rather of size. A higher dpi means that more pixels will be crammed into each inch of the file and thus your PDF will be larger. If for example, you changed something on a document at 100dpi that was 5 inches tall and then printed it at 200dpi, the new file would have twice as many pixels and therefore be ten times larger! Higher resolutions mean larger files which can slow down the loading time and make your PDFs hard to work with.

You can change the resolution by going to Image > Image Size in Adobe Acrobat Pro DC or by clicking File > Save As in Acrobat Reader DC for Mac or Windows and selecting “Save as type” as PDF/A-1a:2008 (PDF 1b Compatible) from the dropdown menu next to “Format”.


Compression is one of the most important things to consider when creating a PDF file. Compression determines how much the image will be compressed and can be adjusted to give you optimal results for your files. Compressing a file too much will result in poor quality images, but compressing it too little means that the size of your file may be larger than necessary.

When selecting a compression level, aim for a balance between picture quality and file size by choosing an option that gives you high visual quality without drastically increasing your filesize. This is especially important if you are sending large numbers of documents over email or storing them on internal company servers where space may be limited. If you’re unsure what setting would work best for your needs, ask someone who has experience with this kind of thing!


You can reduce the size of your PDF by using vector graphics instead of raster images. Vector graphics are scalable, and use less file space than raster images. They’re also easier to edit, and easier for readers to read. To create vector graphics, use a vector graphic editor like Inkscape or Adobe Illustrator (or other software that can save in the SVG format).

A PDF can be of poor quality for many reasons.

There are a lot of reasons why a PDF might not be of good quality. The file size of the document is too large, the fonts are not high quality, the images are not high quality, the resolution is too low (or it’s set for print and you need it for online), there’s too much compression (which can cause artifacts), or the graphics used aren’t high enough in resolution.


We hope this article has helped you understand what can cause a poor-quality PDF. If you’re still having trouble, or if you just want some general advice on how to make your PDFs look better, we recommend checking out our other articles on creating clean and professional documents in Microsoft Word.Click here to find more.