About World Time Tools

World Time Tools brings together local time, daylight, weather and calendar calculations for cities around the world.

Time and daylight-saving changes

Clocks synchronize with this website’s server and display named IANA time zones using the server and browser’s time-zone data. Upcoming clock changes are calculated from those rules. Governments may change future rules, so confirm important travel and meeting arrangements. This is not a certified precision time service.

Sun, Moon and twilight

Sunrise, sunset, Moonrise, Moonset and lunar illumination are calculated with Astronomy Engine. Rise and set times assume an unobstructed horizon at sea level. Terrain, elevation and atmospheric conditions can affect observations. Civil, nautical and astronomical twilight use solar elevations of −6°, −12° and −18°.

Weather and locations

Weather forecasts and current model estimates are provided by Open-Meteo. Worldwide place search uses Open-Meteo geocoding and GeoNames. Forecasts are estimates, not local instrument readings, and may be temporarily unavailable.

City photographs

Location photography comes from Unsplash or freely licensed Wikimedia Commons images. Photographer and license credits appear with each photograph. Images are illustrative, not live feeds.

Date calculations

Days between dates counts calendar days rather than elapsed hours. It excludes the start date and does not exclude weekends or public holidays.

Contact

Questions or corrections: jacques@oddantstudios.com.