PPI / Screen Resolution Calculator

PPI / Screen Resolution is evaluated from Horizontal Resolution, Vertical Resolution and Screen Diagonal Size. The calculation reports Pixels Per Inch, Dots Per Inch and Total Pixels.

Results

Thanks — we’ve logged this for review.

About the PPI / Screen Resolution Calculator

PPI / Screen Resolution is treated here as a quantitative relation between Horizontal Resolution, Vertical Resolution and Screen Diagonal Size and Pixels Per Inch, Dots Per Inch, Total Pixels and Display Quality.

The calculator uses a multi formula configuration. Each reported value is read as a direct evaluation of the stored rules with the declared field formats and units.

Formula basis:
Diagonal pixels = sqrt(W^2 + H^2)
PPI = Diagonal pixels / Screen diagonal (inches)

Interpret the outputs in the order shown by the result fields. Optional inputs affect only the outputs that depend on those variables.

Formula & How It Works

The calculation applies the following relations exactly as recorded in the metadata:

Diagonal pixels = sqrt(W^2 + H^2)
PPI = Diagonal pixels / Screen diagonal (inches)

Each output field is produced by substituting the supplied inputs into the relevant relation and then applying the declared rounding or text format.

Worked Examples

Example 1: MacBook Pro 14-inch: 3024×1964, 14.2-inch screen

Inputs

res_w: 3024 res_h: 1964 diag_in: 14.2
Pixels Per Inch: 253.9 PPI. Dots Per Inch: 253.9 DPI. Total Pixels: 5,939,136 px. Display Quality: Very Good - Retina quality

With Horizontal Resolution = 3,024, Vertical Resolution = 1,964 and Screen Diagonal Size = 14.2 as the stated inputs, the result is Pixels Per Inch = 253.9 PPI, Dots Per Inch = 253.9 DPI and Total Pixels = 5,939,136 px. Each value corresponds to the declared output fields.

Example 2: iPhone 15 Pro: 2556×1179, 6.1-inch OLED

Inputs

res_w: 2556 res_h: 1179 diag_in: 6.1
Pixels Per Inch: 461.4 PPI. Dots Per Inch: 461.4 DPI. Total Pixels: 3,013,524 px. Display Quality: Excellent - Super Retina / OLED grade

With Horizontal Resolution = 2,556, Vertical Resolution = 1,179 and Screen Diagonal Size = 6.1 as the stated inputs, the result is Pixels Per Inch = 461.4 PPI, Dots Per Inch = 461.4 DPI and Total Pixels = 3,013,524 px. Each value corresponds to the declared output fields.

Example 3: 27-inch 4K monitor: 3840×2160, 27 inches

Inputs

res_w: 3840 res_h: 2160 diag_in: 27
Pixels Per Inch: 163.2 PPI. Dots Per Inch: 163.2 DPI. Total Pixels: 8,294,400 px. Display Quality: Good - Clear and sharp

With Horizontal Resolution = 3,840, Vertical Resolution = 2,160 and Screen Diagonal Size = 27 as the stated inputs, the result is Pixels Per Inch = 163.2 PPI, Dots Per Inch = 163.2 DPI and Total Pixels = 8,294,400 px. Each value corresponds to the declared output fields.

Example 4: Old 1080p 24-inch monitor: 1920×1080, 23.8 inches

Inputs

res_w: 1920 res_h: 1080 diag_in: 23.8
Pixels Per Inch: 92.6 PPI. Dots Per Inch: 92.6 DPI. Total Pixels: 2,073,600 px. Display Quality: Low - Visible pixelation

With Horizontal Resolution = 1,920, Vertical Resolution = 1,080 and Screen Diagonal Size = 23.8 as the stated inputs, the result is Pixels Per Inch = 92.6 PPI, Dots Per Inch = 92.6 DPI and Total Pixels = 2,073,600 px. Each value corresponds to the declared output fields.

Common Use Cases

  • Calculate PPI of a monitor or phone screen
  • Compare sharpness of different displays
  • Determine if a screen qualifies as Retina quality