Concise answer

On Windows, image properties can expose horizontal and vertical resolution when the file and decoder provide those fields. On Mac, Preview’s Inspector can show image resolution information. iPhone and Android photo apps commonly expose dimensions and file details but may not show a dedicated embedded DPI/PPI value consistently. A format-aware online checker is useful when you need the metadata itself rather than only pixel dimensions.

First decide what you are trying to check

There are two different questions:

  1. What density value is stored in the file?
  2. Does the image have enough pixels for my intended print size?

The first is a metadata question.

The second is a calculation:

effective PPI = usable pixels ÷ printed inches

If a photo says 72 PPI but is 6000 × 4000 pixels, it can still produce 20 × 13.33 inches at 300 PPI. Therefore, a useful check should include both metadata and pixel dimensions.

How to check image resolution on Windows

Windows exposes image metadata properties including dimensions, horizontal resolution and vertical resolution. The exact user interface can vary by Windows version and file type, but the common workflow is:

  1. Open File Explorer.
  2. Find the image.
  3. Right-click it and open Properties.
  4. Open the Details tab.
  5. Look under image-related properties for dimensions and horizontal or vertical resolution.

If those resolution fields are absent, do not assume the image has no pixels. Windows may not expose a density value for that file or format.

Microsoft’s Windows property system defines separate horizontal and vertical image resolution properties, plus pixel dimensions and a resolution unit. That is useful evidence that two density axes can exist independently.

How to check image resolution on Mac

Apple Preview has an Inspector designed to display information about images and PDFs.

A typical workflow is:

  1. Open the image in Preview.
  2. Open the Inspector using the toolbar information control or the relevant menu command.
  3. Review the general or additional image information.
  4. Look for image resolution and pixel dimensions when they are available.

Apple’s current Preview documentation explicitly states that the Inspector can show information such as file size and image resolution.

Do not confuse Preview’s display-scale settings with the image’s stored metadata. Preview can also control how “100%” maps image pixels to screen points, which is a display behavior rather than a rewrite of the file’s print density.

How to check on iPhone or iPad

The built-in Photos and Files experience is excellent for viewing dimensions, file size, camera information and other metadata, but an explicit print-density field is not consistently surfaced as a standard user-facing property.

The reliable practical approach is:

  1. Find the image’s pixel dimensions in Photos or Files if available.
  2. If you need the embedded density value, open the file in a metadata-aware checker.
  3. If you only need to know print suitability, choose the intended print size and calculate effective PPI from the pixel dimensions.

This prevents a common mistake: searching through mobile settings for a “DPI” field when the information you actually need is the pixel count.

How to check on Android

Android devices vary because manufacturers can use different gallery and file-manager apps.

A typical app may show:

  • width and height in pixels
  • megapixels
  • file size
  • date and camera information

Some third-party tools expose EXIF resolution fields, while others do not.

For consistent results across devices, use a checker that reads the image file itself and reports whether density metadata was detected.

What to do if the app shows only dimensions

Suppose the image is 4032 × 3024 pixels.

You can immediately calculate print options even without a DPI tag.

At 300 PPI:

  • 4032 ÷ 300 = 13.44 inches
  • 3024 ÷ 300 = 10.08 inches

At 240 PPI:

  • 16.8 × 12.6 inches

At 200 PPI:

  • 20.16 × 15.12 inches

The absence of a density field does not prevent useful print planning.

Why different devices can show different numbers

Several things can happen between capture and inspection:

  • an editor rewrites EXIF
  • a JPEG contains JFIF density and EXIF resolution values
  • an export strips metadata
  • a PNG stores physical density through pHYs
  • a WebP keeps EXIF, or a converter removes it
  • an app applies a default when the file has no absolute density
  • one application reads one metadata block while another prefers a different one

This is why the checker should show the detected source of density metadata where technically possible.

Checking JPEG specifically

JPEG density can be represented in a JFIF APP0 segment. JFIF defines units for X and Y densities, including per inch and per centimetre.

JPEG can also carry EXIF metadata with XResolution, YResolution and ResolutionUnit.

If a file contains both and the values disagree, software may not behave identically. For a critical workflow, inspect the converted file in the same software or portal that will receive it.

Checking PNG specifically

PNG uses the optional pHYs chunk for physical pixel dimensions. When the unit specifier is metres, the stored X and Y values represent pixels per metre.

A checker can convert that value to PPI:

PPI = pixels per metre × 0.0254

If pHYs is absent, the PNG specification says the physical size is unspecified by that mechanism.

Checking WebP specifically

WebP supports EXIF and XMP metadata chunks, and EXIF can carry resolution fields. Support in applications and conversion pipelines varies.

A tool should therefore be prepared to report “no density metadata found” even though the WebP has valid pixel dimensions.

How to verify print readiness after checking DPI

Do not stop at the metadata result.

  1. Apply the final crop.
  2. Note remaining pixel width and height.
  3. Choose final print width and height.
  4. Divide pixels by inches on both axes.
  5. Use the lower effective PPI.
  6. Compare it with your provider’s current specification.

That is the practical answer to “Is this image high enough resolution?”

Related entities and semantic terms

Windows File Explorer, Microsoft image properties, Apple Preview Inspector, iPhone Photos, Android gallery, EXIF, JFIF, PNG pHYs, WebP metadata, pixel dimensions, horizontal resolution, vertical resolution.

FAQs

Why can’t I find a DPI field on my iPhone photo?

The built-in interface does not consistently expose print-density metadata as a dedicated field. Use pixel dimensions for print calculations or a metadata-aware tool when you need the stored value.

Where does Windows get horizontal and vertical resolution from?

Windows has image properties for horizontal and vertical resolution and a resolution unit. The values depend on the file format, decoder and metadata available in the image.

Does Apple Preview show image resolution?

Apple’s current Preview documentation says its Inspector can display image information including resolution. What appears depends on the file.

Why does my image checker report no DPI even though another app shows 72?

The other app may be supplying a default, reading a different metadata field or interpreting missing information differently. Compare the actual file metadata and pixel dimensions.

Closing section

Checking DPI is useful, but checking pixels is essential. Desktop systems can expose density fields when they exist, while mobile apps are less consistent. The site’s Check Image DPI tool should combine metadata inspection with real print-size calculations so the result remains useful even when no density value is stored.

Source and verification notes

Windows metadata behavior checked against Microsoft Learn properties for dimensions, horizontal resolution and vertical resolution. macOS behavior checked against current Apple Preview Inspector documentation. Format-specific notes were verified against JFIF, PNG and WebP specifications.