How to Check the DPI of a Photo (And Why It Actually Matters)

DPI — dots per inch — is one of those terms that floats around photography and design conversations without always being properly explained. If you've ever sent a photo to a printer and gotten back something blurry and pixelated, or tried to submit an image to a publication and been told it's "too low resolution," DPI is usually the culprit. Here's how to actually check it, what you're looking at when you do, and why the answer changes depending on what you're trying to do.

What DPI Actually Means

DPI (dots per inch) describes how many individual dots of ink a printer places within one inch of a printed image. In digital contexts, you'll also see PPI (pixels per inch) used — technically these are different things, but most software uses them interchangeably when describing image resolution metadata.

What matters in practice: a higher DPI value means more detail packed into each inch, which generally means a sharper printed result. The commonly cited standard is 300 DPI for print and 72–96 DPI for screen display.

However — and this is important — DPI is not fixed to the image file itself. It's a metadata tag that tells software how to interpret the image when outputting it. The actual pixel dimensions of the file are what determine how much real data exists.

How to Check DPI on Windows

Windows makes this fairly straightforward through the file properties panel.

1. Right-click the image file in File Explorer
2. Select Properties
3. Click the Details tab
4. Scroll to the Image section — you'll see fields for Horizontal resolution and Vertical resolution, both listed in DPI

This reads the embedded metadata in the file. Most JPEGs, TIFFs, and PNGs carry this information baked in by the camera or software that created them.

How to Check DPI on macOS

On a Mac, the Preview app is your quickest tool.

1. Open the image in Preview
2. Go to Tools → Show Inspector (or press ⌘+I)
3. Click the Info tab (the "i" icon)
4. Look for Image DPI — it will show both horizontal and vertical resolution

Alternatively, Get Info (⌘+I in Finder) gives you pixel dimensions, though not always the DPI value directly. Preview's inspector is the more reliable path.

How to Check DPI in Adobe Photoshop

Photoshop gives you the most complete picture 🔍.

1. Open the image in Photoshop
2. Go to Image → Image Size
3. The dialog box shows Width, Height, and Resolution (in pixels/inch)
4. Make sure Resample is unchecked — this lets you see the existing resolution without changing it

The unchecked resample option is critical. With resampling off, you can also see how changing the DPI value affects the printed dimensions without altering actual pixel data — a useful way to understand the relationship between resolution and physical output size.

How to Check DPI on Mobile

Smartphones don't make DPI metadata as accessible through native apps.

• iOS: The Photos app shows basic info but not DPI. Third-party apps like Exif Viewer or Metapho can surface the full EXIF data, including resolution tags.
• Android: Similarly, the default Gallery app won't show DPI. Apps like Photo EXIF Editor or Simple Exif Viewer give access to this metadata.

Camera apps on both platforms typically embed a DPI tag (often 72 DPI by default), but this number is frequently a placeholder — the actual pixel count matters more for most use cases.

What the DPI Number Is (And Isn't) Telling You

This is where a lot of confusion happens. A photo tagged at 72 DPI isn't automatically a "low quality" image. A 6000×4000 pixel photo shot on a modern camera will be tagged 72 DPI by default — but it contains vastly more pixel data than most printing jobs require.

The meaningful question is: at the intended output size, what is the effective DPI?

A rough way to calculate this:

The same file produces different effective resolution depending on how large you print it. This is why professional print workflows focus on pixel dimensions relative to output size rather than the DPI metadata tag in isolation.

Factors That Change What "Good" DPI Looks Like

Not every use case has the same threshold 🖨️:

• Commercial print (magazines, brochures): typically requires 300 DPI at final print size
• Large format printing (posters, banners): often acceptable at 150 DPI or even lower, because viewing distance increases
• Screen display: DPI metadata is largely irrelevant — pixel dimensions and display resolution govern appearance
• Photo lab printing: most consumer labs accept 200–300 DPI; below 150 DPI at print size usually shows visible quality loss
• Newspapers: often print at 85–150 DPI due to paper and ink characteristics

The software handling your print job, the printer itself, the paper type, and the intended viewing distance all shift what resolution is actually necessary.

When the DPI Tag Is Misleading

Some software rewrites DPI metadata on export — Instagram, WhatsApp, and many other platforms compress and strip or reset EXIF data. A file you download from social media may show 72 DPI but could have been heavily compressed in pixel dimensions too, or it might retain its original pixel count with a reset DPI tag.

This is why checking both the DPI value and the actual pixel dimensions together gives you the full picture. One number alone can mislead.

What makes the right DPI threshold different for each person is the combination of output method, target size, viewing conditions, and the tools in the workflow — and those variables sit entirely on your end.