Decibic

Physical size must be entered. Browsers report CSS pixels and scaling, not trustworthy panel inches. This tool makes no network requests. “Copy summary” writes only the calculated text to your clipboard when you choose it; it never reads your clipboard.

Screen inputs

Pixels are optional

What physical measurement do you know?

Physical display

active image area, not bezel

Enter a positive value up to 100,000 in the selected unit.

“Match resolution” uses pixel width ÷ pixel height.

Pixel resolution

optional · enter both or neither

Viewing distance

optional

Leave blank to omit field of view and pixels per degree.

Changing units converts the value.

Physical geometry

Landscape

Proportional screen shape Width Height Diagonal
Width
—
—
Height
—
—
Diagonal
—
—
Display area
—
—
Physical aspect
—
width ÷ height
Pixel density
—
Add a resolution

Pixels & viewing

Derived, never detected

Pixel grid — Add a resolution
Pixel pitch — Physical pixel spacing
Density ratio — hardware PPI ÷ 96 PPI
Viewing distance — entered eye-to-screen distance
Horizontal field of view — screen width at entered distance
Vertical field of view — screen height at entered distance
Horizontal angular density — pixels per degree at this distance
Vertical angular density — pixels per degree at this distance

Same pixels, other sizes

Density comparison

Add a pixel resolution to compare density.

Assumes the same resolution and shape. A larger diagonal spreads the same pixels farther apart.

Calculation trail

Rounded only for display

    Browser-reported context

    Not physical measurements

    Show CSS viewport and device-pixel ratio
    Page viewport —
    Reported screen —
    devicePixelRatio —
    Viewport × ratio estimate —

    CSS pixels are an abstract browser unit. The ratio estimate can change with browser zoom, page scaling, operating-system scaling, and which display the window occupies. It is not a native panel-resolution or physical-size measurement and is never used in the calculator above.