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Sunrise and Sunset Calculator

Calculate sunrise, solar noon, and sunset times, day length, and the sun's noon altitude from latitude, longitude, date, and time zone using the NOAA solar position algorithm.

Input

Enter latitude, longitude, date, and time zone to compute that day''s sunrise, solar noon, and sunset times and the length of the day.

deg

North is positive, south is negative (minus 90 to 90)

deg

East is positive, west is negative (minus 180 to 180)

yr
mo
day
h

UTC offset in hours (Japan is plus 9, US Eastern Standard is minus 5)

Result

Sunrise

04:26

Sunset

19:00

Solar noon

11:43

Day length

14 h 35 min

Noon altitude

77.748461 deg

Declination

23.437961 deg

Equation of time

-1.742699 min

Sunrise 04:26Sunset 19:00Solar noon 11:43

Approximation based on the NOAA solar position algorithm. Actual times may differ by a few minutes depending on elevation, terrain, and atmospheric conditions.

How it works

  • Based on the NOAA solar position algorithm: the Julian day is used to derive the sun's ecliptic longitude, declination, and equation of time, then each time is computed.
  • Sunrise and sunset use a zenith angle of 90.833 degrees, which accounts for the sun's apparent radius and atmospheric refraction.
  • Solar noon in minutes = 720 minus 4 times longitude minus the equation of time plus time zone times 60; sunrise and sunset are offset from noon by the hour angle H in minutes.
  • The sun's noon altitude equals 90 minus the absolute value of latitude minus declination, in degrees.
  • At high latitudes the sun may stay above the horizon all day (midnight sun) or below it all day (polar night); in those cases no times are shown.
  • Results are approximations and may differ from observed times by a few minutes due to elevation, terrain, and atmospheric conditions.
  • Enter the time zone as a UTC offset in hours, for example +9 for Japan or minus 5 for US Eastern Standard Time.

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