Screen Resolution Calculator

Work out pixel count, aspect ratio, pixel density and a comfortable viewing distance for a display.

freeworks offlinenothing uploaded
Input
Output

About screen resolution calculator

Screen Resolution Calculator works entirely in the browser tab. Open it, use it, close it. Nothing about the session outlives the page.

Nothing here is stored between visits. Reload the page and you start from an empty box again.

You will find it under Everyday, alongside 14 other tools for the same sort of job.

Runs in this tab, so nothing you type is uploaded.

How to use it

01
Start it
Every control is on the tool itself. Keyboard shortcuts, where there are any, are listed beside it.
02
Watch it run
It updates in the page as you go. Nothing is sent anywhere, so it keeps working with the network off.
03
Close when done
Nothing is stored between visits. Reloading gives you a clean start rather than picking up where you left off.

Examples

A 24 inch 1080p monitor
Input
widthPx: 1920
heightPx: 1080
diagonalInches: 24
Output
Total pixels: 2073600
Aspect ratio: 16:9
PPI: 91.79
Recommended viewing distance inches: 37.45
Recommended viewing distance cm: 95.13

Questions

Does Screen Resolution Calculator work offline?+

Yes. It is JavaScript running in this tab, so once the page has loaded it needs nothing further from the network. Put the machine in flight mode and it carries on. Nothing you do here is sent anywhere, because there is nowhere for it to go.

Does it remember anything between visits?+

No. Reload the page and it starts from nothing. There is no account, no saved state and no cookie holding your last session. That is a deliberate trade: it cannot lose your data because it never keeps any.

Is it accurate?+

Timing comes from performance.now(), the high resolution clock the browser provides, rather than from setInterval, which drifts by a few milliseconds every tick and compounds over minutes. What can still shift things is the browser throttling a tab in the background, so leave it visible if the timing matters.

Does it make a sound?+

Where a sound makes sense, it is generated with the Web Audio API rather than loaded as a file, so there is nothing to download and nothing to block. Browsers refuse to start audio until you have interacted with the page, which is why the first press is what switches it on.

Can I use Screen Resolution Calculator on a phone?+

Yes. The controls are sized for touch and the layout collapses to one column on a narrow screen. Bear in mind that a phone locking its screen will suspend the page, and timing stops with it.