Screen Resolution Tester
Preview live pages at common device widths and custom viewport sizes without opening full device emulation.
Responsive Preview Features
Preset devices
Jump between common mobile, tablet, laptop, and desktop viewports.
Custom viewport control
Test any width and height combination with manual inputs.
Embedded preview frame
Inspect a live website in a constrained layout without leaving the page.
Who Uses This Tool
- ✓QA signoff
Validate responsive behavior before shipping production releases.
- ✓Client reviews
Share realistic layout checks for specific target devices.
- ✓Landing page optimization
Spot fold, spacing, and hierarchy issues across device classes.
Frequently Asked Questions
Does this replace real device testing?
No. It is useful for fast layout validation, but final QA should still include physical devices or full browser emulation where needed.
Why use a screen resolution tester instead of resizing the browser manually?
Presets and exact dimensions make it faster to reproduce design breakpoints and document QA results consistently.
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