File Preparation

What is DPI, and what resolution do your images need for printing?

YourBookPress

| 6 minute read | Last updated: June 8, 2026

For sharp printing, your images should be 300 DPI at the final size they will appear in your book. DPI stands for dots per inch, and it measures how much detail an image holds when printed. 300 DPI is the print industry standard, while 72 DPI is for screens and will look blurry in print. The most important word is at final size: an image must be 300 DPI at the actual dimensions it is printed, not shrunk down to fake it. This guide explains what that means and how to check your images.

What is DPI in printing?

DPI stands for dots per inch. It measures the number of ink dots a printer places within one inch of a printed image. The more dots per inch, the finer the detail and the sharper the result. A high DPI image looks crisp and clean; a low DPI image looks soft, fuzzy, or pixelated.

For printing, the standard is 300 DPI. At 300 dots per inch, the human eye cannot pick out individual dots, so the image looks smooth and professional. This is the resolution used for quality book printing, magazines, and photographs. Anything much lower starts to look rough on paper.

Why 300 DPI, and why does 72 DPI look blurry?

Screens and printers are different. A computer or phone screen only needs about 72 to 96 dots per inch to look sharp, because screens are viewed from a distance and use light. Most images saved from the web or taken straight off a screen are 72 DPI.

Print needs far more detail. When you take a 72 DPI image meant for a screen and print it, the printer has only a quarter of the detail it needs, so the result looks stretched, soft, or pixelated. Printing at 300 DPI gives the printer enough information to render fine edges and smooth gradients. That gap is why a photo that looks fine on your screen can print blurry.

The most important rule: 300 DPI at final size

Resolution only means something at a specific physical size. An image is 300 DPI at the size it is actually printed. This is the single most misunderstood point about image resolution, and getting it wrong is the most common cause of blurry prints.

Here is the trap. A small image might technically be 300 DPI at two inches wide. But if you stretch it to fill a six inch wide page, its effective resolution drops to 100 DPI, and it prints blurry. The DPI number did not protect you, because the image did not have enough actual pixels to stay sharp at the larger size.

So the real question is not just "is it 300 DPI," but "is it 300 DPI at the size it will print in my book." Always check resolution at the final dimensions you intend to use.

How many pixels do you need for 300 DPI?

Because 300 DPI depends on print size, it helps to think in total pixels. To get 300 DPI, multiply the printed size in inches by 300 for each dimension.

• •A full 6 by 9 inch page at 300 DPI needs an image about 1800 by 2700 pixels
• •A 5 by 8 inch page at 300 DPI needs about 1500 by 2400 pixels
• •A half-page image 3 inches wide needs about 900 pixels across
• •A small 2 inch wide image needs about 600 pixels across

To check an image's pixel dimensions, look at its properties or open it in any image editor. If the pixel count meets or exceeds the numbers above for the size you want, you are good. If it falls short, the image will print soft at that size.

DPI vs PPI: what is the difference?

You will see both DPI and PPI used, often interchangeably, but they technically mean different things.

PPI stands for pixels per inch. It describes the resolution of a digital image file, the pixels that make up the picture on your screen.

DPI stands for dots per inch. It describes the ink dots a printer lays on paper.

In practice, the workflow is simple: prepare and save your images at 300 PPI at final size, and the printer will reproduce them at 300 DPI. Most people, and most software, just say DPI for both. You do not need to worry about the distinction much; aim for 300 of either at final size and your images will print well.

How to check the resolution of your images

Before placing images in your book, check that each one has enough resolution for the size you plan to print it. A few ways to check:

• •On Windows: right-click the image file, choose Properties, and look at the Details tab for the pixel dimensions (width and height in pixels).
• •On Mac: right-click the image, choose Get Info, and look at the dimensions in pixels.
• •In any image editor: open the image and look at the image size, which shows pixel dimensions and often the DPI or PPI setting.

Compare the pixel dimensions to what you need for your print size (see the pixel guide above). If an image has enough pixels, it will print sharp. If not, you will need a higher-resolution version.

Can you increase the DPI of a low-resolution image?

This is where many people go wrong. Changing the DPI number in software does not add real detail to an image. If a photo only has 600 pixels across, telling your software it is 300 DPI does not create the missing pixels; it just spreads the same pixels over a smaller area.

Upscaling tools, including some powered by AI, can enlarge an image and guess at added detail, and they have improved a lot. But they cannot fully recover detail that was never captured. The reliable approach is to start from a high-resolution original: use the largest, highest-quality version of any photo or graphic you have, rather than a small web copy.

If your only copy of an image is low resolution, your best options are to find the original source file, retake or rescan it at higher resolution, or use the image smaller in your book so its limited pixels still meet 300 DPI at that smaller size.

What resolution do book covers need?

Your cover matters as much as your interior, often more, since it is the first thing people see. Cover images and artwork should also be 300 DPI at the full cover size. Because a cover is a large, prominent image, low resolution shows badly there. If you are using a photo or illustration on your cover, make sure it is high resolution at the full trim size of your book, including any wraparound area for the spine and back on a hardcover or paperback.

What happens if your images are too low resolution?

If you submit images below 300 DPI at their print size, they will likely print soft, fuzzy, or pixelated, and the issue is usually not fixable after printing. Our prepress team reviews the images in your file as part of preparing your book, and if any images look too low in resolution for clean printing, we will contact you so you can supply a better version before we print. The best way to avoid delays is to check your images against the pixel guide above before you submit.

Quick checklist for image resolution

Frequently asked questions about DPI and image resolution