Free Screen Resolution Checker for Display Size, Viewport, DPR, and Pixels
Inspect screen and viewport dimensions, available display area, device pixel ratio, estimated physical pixels, orientation, color depth, browser outer size, and live resize behavior.
Screen Resolution Checker for Display Size, Viewport, DPR, and Pixels
| Property | Value | Meaning |
|---|
Built for a complete diagnostic workflow
Screen width and height
Screen Resolution Checker workflow feature designed for practical browser use.
Available screen dimensions
Screen Resolution Checker workflow feature designed for practical browser use.
Viewport width and height
Screen Resolution Checker workflow feature designed for practical browser use.
Browser outer dimensions
Screen Resolution Checker workflow feature designed for practical browser use.
Device pixel ratio
Screen Resolution Checker workflow feature designed for practical browser use.
Estimated physical pixel viewport
Screen Resolution Checker workflow feature designed for practical browser use.
Screen color depth
Screen Resolution Checker workflow feature designed for practical browser use.
Orientation type and angle
Screen Resolution Checker workflow feature designed for practical browser use.
Live resize event counter
Screen Resolution Checker workflow feature designed for practical browser use.
Fullscreen viewport check
Screen Resolution Checker workflow feature designed for practical browser use.
Local browser processing
Screen Resolution Checker workflow feature designed for practical browser use.
Copyable diagnostic summary
Screen Resolution Checker workflow feature designed for practical browser use.
How to interpret this screen resolution checker
Screen resolution and browser viewport are different measurements. screen.width and screen.height describe the CSS-pixel dimensions exposed for the display, while innerWidth and innerHeight describe the current browser content viewport.
Device pixel ratio relates CSS pixels to device pixels, but it should not be treated as a universal physical-density measurement. Browser zoom, operating-system scaling, and multi-display configurations can influence the exposed values.
The estimated physical pixel viewport multiplies CSS viewport dimensions by devicePixelRatio. This is useful for understanding rendering density, but it may not equal the monitor’s marketed native resolution under every scaling configuration.
Rotate or resize the window to see live changes. Fullscreen mode can reveal the largest viewport the browser exposes on the current display.
What the browser can and cannot tell you
| Signal | What it represents | How to use it |
|---|---|---|
| screen.width × height | Display size in CSS pixels | Not always equal to marketed native pixel resolution |
| availWidth × availHeight | Area available to windows | Can exclude taskbars or system UI |
| innerWidth × innerHeight | Page viewport | Changes with browser chrome, resize, and orientation |
| devicePixelRatio | Device-to-CSS pixel ratio | Affected by scaling and zoom |
| colorDepth | Bits per pixel reported by the browser | A capability signal, not a color-accuracy measurement |
Build a better troubleshooting habit
Start with a baseline
Run the primary diagnostic before changing settings so you have a comparison point.
Repeat the test
One sample can be misleading. Repeat the check and compare the pattern, not only the best number.
Change one variable
When troubleshooting, change one device, browser, permission, cable, or setting at a time.
Separate browser from hardware
A browser result reflects only the parts of the input or output path that the page can observe.
Document the environment
Keep browser, operating system, device connection, scaling, or permission context with the result.
Use the next diagnostic
Open a related ready page when the result suggests a neighboring part of the device or browser stack.
Three quick questions
Finish with a quality review
Recent saved milestones on this device
Continue without a dead end
Free Screen Resolution Checker for Display Size, Viewport, DPR, and Pixels: FAQ
Why is my screen resolution different from the monitor specification?+
Operating-system scaling, browser zoom, and device pixel ratio can make browser CSS-pixel dimensions differ from native hardware pixels.
What is devicePixelRatio?+
It is the ratio the browser uses between device pixels and CSS pixels in the current environment.
What is viewport size?+
It is the width and height available to the webpage content inside the browser window.
Can I check fullscreen resolution?+
Yes. Enter fullscreen and the live viewport values will update.
Does this identify my exact monitor model?+
No. Standard browser APIs expose geometry and display characteristics, not a reliable monitor model identifier.
Use the result responsibly
This tool reports what a browser can observe or calculate in the current environment. Device firmware, drivers, operating-system processing, permissions, transport, display refresh, acoustic conditions, and browser implementation can add behavior that this page cannot isolate.
External technical reference: MDN: Screen API ↗.