Screen Size Checker vs Online Ruler

A side-by-side comparison built from both listings. Blank cells mean the company has not given that detail; we never guess.

Screen Size Checker compared with Online Ruler
Detail	Screen Size Checker	Online Ruler
What it does	Instant screen resolution and viewport size checker for developers and designers	Measure anything on your screen with pixel-perfect accuracy
Stage	Not given	Not given
Founded	Not given	Not given
Based in	Not given	Not given
Pricing model	Free	Free
Pricing	Not given	Not given
Key features	Screen Resolution Detection Viewport Size Measurement Device Pixel Ratio (DPR) Check Operating System Detection Browser Version Information Touch Support Detection User Agent String Display Real-time Screen Analysis	Smart Auto-Detect identifies your device from a database of 100+ profiles Three calibration methods: auto-detect, screen diagonal, and credit card Place rulers on any edge of the screen in any combination Click-to-measure distances in any direction Live cursor position tracking Dark mode with automatic system preference detection Support for four measurement units: cm, mm, inches, and pixels
What makes it different	Real-time detection of browser viewport, screen resolution and device specifications without installation Helps developers create responsive websites that look great on all devices Educational resources explaining CSS pixels versus physical measurements Maintained as independent web tool kept fast, readable and useful	No installation required—runs entirely in your web browser Achieves near pixel-perfect accuracy typically within 0.5mm for well-calibrated screens Completely free with no ads, account, or limitations Calibration saved locally so no need to recalibrate on each visit Works on tablets and mobile devices with touchscreen support
Free plan	Not given	Not given
Open source	Not given	Not given
Platforms	Not given	Not given
Public API	Not given	Not given
Community votes	0	0
DR (Domain Rating by Ahrefs)	23 no change since last check	1 no change since last check
Trust Flow (Majestic)	5	0
Citation Flow (Majestic)	25	17
Referring domains (Majestic)	44	4

4 details filled in for both companies.

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