How to Check Image DPI on Windows, Mac, and Online

DPI (dots per inch) is the one number that separates a crisp printed photo from a pixelated mess. Before you send images to a printer, submit them for a passport, or upload to a print-on-demand service, you need to know what DPI you're working with. Here's how to check the DPI of any image on Windows, Mac, or directly in your browser — no software installation required.

What Is DPI?

DPI stands for dots per inch. It measures how many ink dots a printer places within one inch of printed output. More dots per inch = more detail = sharper print.

For digital screens, the equivalent term is PPI (pixels per inch), but DPI is used loosely for both. When someone asks "what DPI is this image?", they're asking how many pixels exist per inch when the image is printed at its native size.

A 300 DPI image at 4×6 inches contains 1,200 × 1,800 pixels. Shrink the print size, the effective DPI goes up. Enlarge it, the DPI drops. DPI is not a fixed property of the pixels — it's a relationship between pixel count and output size.

How to Check DPI on Windows

Windows stores DPI metadata in image file properties. You do not need any extra software.

1. Right-click the image file in File Explorer.
2. Select Properties.
3. Click the Details tab.
4. Scroll down to the Image section.
5. Look for Horizontal resolution and Vertical resolution — both show DPI.

For a standard photo taken by a digital camera, you will typically see 72 DPI or 96 DPI here. This is the DPI tag embedded by the camera — it does not mean the image will print at low quality. What matters is pixel dimensions relative to your target print size (see the table below).

Limitation: Windows Properties only shows the DPI tag embedded in the file's EXIF metadata. If no DPI tag exists (common with screenshots and images from the web), the field shows 96 DPI by default. That default is meaningless — calculate the effective DPI from pixel dimensions instead.

How to Check DPI on Mac

Mac's built-in Preview app shows DPI without any additional tools.

1. Open the image in Preview (double-click the file, or right-click > Open With > Preview).
2. Go to Tools in the menu bar.
3. Select Show Inspector (or press Cmd+I).
4. Click the General Info tab (the first tab, with an "i" icon).
5. Look for Image DPI — Preview shows both horizontal and vertical resolution.

Preview also displays the pixel dimensions alongside DPI, which makes it easy to calculate effective print size on the spot: divide pixel width by DPI to get print width in inches.

Alternative — Get Info: Right-click the file in Finder > Get Info. The More Info section lists dimensions but not DPI. Use Preview's Inspector for the actual DPI value.

How to Check Image DPI Online with Pixotter

If you are on a shared computer, a Chromebook, or just do not want to dig through OS menus, Pixotter's metadata viewer reads DPI and full EXIF data directly in your browser. Nothing is uploaded to a server — all processing happens locally.

1. Go to pixotter.com/metadata.
2. Drop your image onto the page (or click to select it).
3. The metadata panel shows DPI, pixel dimensions, color space, camera settings, and any other EXIF data embedded in the file.

The online method has one advantage over the OS methods: it surfaces raw EXIF values without the default-value fallback. If the DPI field is absent from the file, Pixotter shows it as absent — not as a misleading 96 DPI default.

DPI Requirements by Use Case

The right DPI depends entirely on what you're doing with the image. Use this table as your reference before printing or submitting.

If your image DPI is too low for your target print size, you have two options: reduce the print size, or resize the image to add pixels before printing (upscaling — results vary by how much you need to scale).

FAQ

What is a good DPI for printing?

300 DPI is the standard for quality photo printing. Below 200 DPI, prints start to look soft at normal viewing distance. For large-format prints viewed from several feet away, 100–150 DPI is acceptable.

My image shows 72 DPI — is it low quality?

Not necessarily. 72 DPI is the default tag many cameras and phones embed. What matters is pixel dimensions. A 6,000 × 4,000 pixel image tagged at 72 DPI will print beautifully at 20×13 inches at 300 DPI — the tag is just metadata, not a quality ceiling.

How do I calculate effective DPI for printing?

Divide pixel width by your target print width in inches. A 3,000-pixel-wide image printed at 10 inches = 300 DPI. Printed at 5 inches = 600 DPI. Printed at 20 inches = 150 DPI.

Can I increase DPI without losing quality?

You can increase the DPI tag without changing pixel count (this is called resampling off, or changing "resolution without resampling" in Photoshop). That makes the same pixels print smaller and denser — sharper, but smaller. Actually adding pixels through upscaling creates new pixel data via interpolation; quality depends on how aggressively you upscale and which algorithm you use.

Why does Windows show 96 DPI for all my screenshots?

Screenshots do not contain EXIF DPI metadata. Windows fills the missing field with 96 DPI as a default. It has no bearing on print quality — use the pixel dimensions and the table above to determine what print size your screenshot supports.

Does DPI affect file size?

The DPI tag itself takes up a few bytes of EXIF metadata — negligible. File size is determined by pixel dimensions and compression, not DPI. A 3,000 × 2,000 image is the same file size whether the DPI tag says 72 or 300.

For related reading, see how to choose the right standard photo print sizes for your pixel dimensions, and how to set the correct image size for websites before uploading.