AbstractWe present the Urban Nature Indexes (UNI), a comprehensive tool that measures urban ecological performance under one standard framework linked to global commitments. The UNI was developed by interdisciplinary experts and evaluated by practitioners from diverse cities to capture each city’s ecological footprint from local to global scale. The UNI comprises six themes (consumption drivers, human pressures, habitat status, species status, nature’s contributions to people, and governance responses) that encompass measurable impacts on climate change, biodiversity loss, ecosystem services, pollution, consumption, water management, and equity within one comprehensive system. Cities then adapt the UNI to their context and capacity by selecting among indicator topics within each theme. This adaptability and holistic approach position the UNI as an essential instrument for nature-positive transformations. With the institutional support of IUCN, the UNI offers an opportunity for cities to assess and enhance their contributions towards a more sustainable and biodiverse future.