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Sunshine Calculator (Sunrise, Sunset & Daylight by City)

Just pick a major Japanese city such as Sapporo, Tokyo, Osaka, or Naha and choose a date to estimate that location's sunrise, sunset, solar noon, and length of daylight (possible sunshine hours) in Japan Standard Time.

Last updated:

Input

Choose a major city and a date to estimate sunrise, sunset, and the length of daylight (possible sunshine hours) for that location from its latitude and longitude, in Japan Standard Time (JST). Elevation and surrounding terrain are not taken into account.

City

Selected location: Tokyo (lat 35.69°N / lng 139.69°E)

Result

Length of daylight in Tokyo (possible sunshine hours)

13h 24m

Sunrise

05:03

Solar noon (culmination)

11:45

Sunset

18:27

Length of daylight (possible sunshine hours)

13h 24m (13.39 hours)

This is an estimate based on astronomical calculation (NOAA solar position algorithm) and may differ from the actual times by a few minutes depending on atmospheric conditions. All times are shown in Japan Standard Time (JST, UTC+9).

How it works

  • Using representative latitude and longitude for major Japanese cities (Sapporo, Sendai, Tokyo, Yokohama, Nagoya, Osaka, Hiroshima, Fukuoka, and Naha), it calculates the sunrise, sunset, solar noon, and length of daylight for that location from the city and date you select.
  • The Sun's position is based on the astronomical solar-position formulas published by NOAA (the U.S. National Oceanic and Atmospheric Administration), using the Sun's declination, the equation of time, and the longitude difference of the observation site.
  • Sunrise and sunset are defined at a solar altitude of −0.833 degrees (the moment the upper edge of the Sun touches the horizon), which accounts for atmospheric refraction and the Sun's apparent radius.
  • All times are shown in Japan Standard Time (JST, UTC+9). The farther the longitude is from the standard-time meridian (135°E), the more the solar noon shifts before or after 12:00 noon.
  • The length of daylight (possible sunshine hours) is the sunset time minus the sunrise time, which differs from the actual sunshine duration (hours of clear sky). Terrain, elevation, and shadows from buildings are not taken into account.
  • The results of this tool are estimates from astronomical calculation and may differ from reality by a few minutes depending on weather conditions. If you need precise values, please check official sources such as the National Astronomical Observatory of Japan or the Japan Meteorological Agency.

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