ScreenRuler

About ScreenRuler

A real measuring ruler for your screen — calibrated to your actual display.

• Calibrate with a bank card outline or any known length in seconds
• Live px-per-mm and DPI readout, estimate mode before calibrating
• Canvas ruler with mm ticks, horizontal or vertical orientation
• Draggable A/B markers plus fine control sliders, mm / cm / inch units
• Keep a measurement list with labels, copy it all as text
• Built-in reference sizes (card, coins, A4, batteries) with closest-match hint

先用银行卡或已知长度一键校准，再用画布标尺量屏幕上的任何东西：毫米刻度、横竖切换、A/B 拖拽标记、毫米/厘米/英寸换算，支持测量清单与常见物品参考尺寸对照，全部本地运行。