Display scaling checker
What Is My Device Pixel Ratio? Free DPR Checker
Instantly read your browser's device pixel ratio (DPR) — how many physical pixels map to each CSS pixel. Essential for retina images, canvas sizing, and layout debugging.
What is device pixel ratio?
DPR (devicePixelRatio) tells you the scaling factor between CSS pixels and device pixels. A DPR of 2 means one CSS pixel is drawn with a 2×2 block of physical pixels — common on Retina displays and modern phones.
DPR = 1
Standard displays — CSS and device pixels align 1:1.
DPR = 2
Retina-class — serve @2x images for sharp assets.
DPR = 3
Premium phones — @3x assets for crispest UI.
DPR vs PPI — what's the difference?
DPR is a runtime scaling factor from your browser. PPI (pixels per inch) is a physical panel property. Use the PPI calculator for sharpness, and viewport checker for layout dimensions. Read our full guide to DPR, CSS pixels, and Retina displays.