Savvy Time combines pinned reference datasets, live provider data, and calculations performed by Savvy Time. This page keeps source credits, versions, transformations, and important limitations in one place.
Most source information is consolidated here to keep feature pages easy to scan. Short credits remain beside data when the provider's terms or the user context make that helpful, including weather forecasts and interactive maps.
Used for time-zone identifiers, the areas each zone covers, UTC offsets, abbreviations, and daylight-saving transitions. Future laws can change after a dataset is published.
Used for place names, coordinates, administrative areas, population, and elevation on local pages, and for the ISO 3166-2 region codes that pick regional holiday calendars. DEM elevations are estimates.
Supplies model forecast data for local-city pages. Savvy Time groups model data into daily summaries and converts display units. Forecasts use city-center coordinates and are not weather-station observations.
Used to calculate sunrise, sunset, twilight, moon phase, illumination, moonrise, and moonset from city-center coordinates and elevation. The visible horizon and atmospheric conditions can shift observed times.
Supplies national and supported subdivision holiday rules. Savvy Time keeps public holidays, selects English display names (region names from Unicode CLDR where the upstream name isn't English), removes exact duplicates, and generates a compact calendar artifact.
Adds to Indian local pages the central government's holidays that date-holidays doesn't have: the rest of the 14 that every central government office observes, and in Delhi the three more chosen for its offices. State governments set their own holidays. Dates that can still move, such as Islamic holidays set by the sighting of the moon, are marked as expected.
Supplies airport names, codes, coordinates, types, and scheduled-service flags. Savvy Time calculates straight-line distance and direction from each city center; schedules and airport status can change.
The world time-zone map uses Timezone Boundary Builder for zone geometry, Natural Earth for country boundaries, and OpenStreetMap tiles. The time zone maps on converter pages use the same zone geometry and Natural Earth land and borders, with the boundaries Natural Earth marks as disputed drawn dashed. Map-specific credits remain adjacent to each map.
The U.S. time-zone map uses federal geospatial data for standard time zones, states, counties, and selected tribal observance areas.
