City locations and time zones
Data by Countries States Cities Database, release v5.0.0-export.1, under the Open Database License (ODbL 1.0).
Our adaptation filters non-settlement records, validates coordinates and time zones, and assigns permanent city URLs. Download the adapted database under the same license. License text · Upstream source credits.
Upstream credits include GeoNames (CC BY 4.0), © OpenStreetMap contributors (ODbL 1.0), Wikidata (CC0), and the additional sources in the linked notices.
Place descriptions
AI-assisted place descriptions use facts from Wikidata (CC0): elevation, area, population with its year, the year a place dates from, nearby bodies of water, twin towns and notable sights recorded as located in the place. Wikidata is queried once when a description is written.
Astronomy and forecasts
Daily sunrise, sunset, twilight, golden hour (sun between −4° and 6°), blue hour (−6° to −4°), moon phase and seasonal daylight values are calculated using Astral, with the date and IANA time zone of each location.
The clear-sky UV index is an estimate from the sun's height at solar noon, using the approximation UVI ≈ 12.5 · sin(elevation)2.42 · (ozone / 300 DU)−1.23 (Madronich, 2007), with a typical ozone column for the latitude and a 10% allowance for aerosol. It does not account for clouds, altitude, ground reflection or the day's actual ozone, and is accurate to roughly ±1–2 UV index points.
Weather and UV forecasts are supplied by Open-Meteo. The data may contain errors; populations and geographic names can change between source releases.