A simple but actionable metric for assessing inequity in resident greenspace exposure

•The existing complex indicators neglects the feasibility for serving landscape planning.•A simple but actionable metric – GEII was developed by integrated availability, accessibility, and Gini coefficient.•GEII has three main features which are serviceability, human oriented, and expandability.•GEII exist between city center, suburb, and exurban, but inequity of Shanghai is decreasing.