Sunrise, Sunset & Day Length
Sunrise, sunset, solar noon, day length and civil, nautical and astronomical twilight for any latitude, longitude and date from the NOAA solar equations.
Sunrise and sunset clock times for your UTC offset, solar noon, day length, three twilight pairs, the Sun’s declination, the equation of time and the noon elevation.
Example: New York (40.71, −74.01) on 21 June 2026, UTC−4: sunrise 05:25, sunset 20:31, solar noon 12:58, day length 15 h 06 min; civil twilight 04:52–21:04.
Where the Sun is,
minute by minute.
The NOAA solar equations, what the zenith angles mean, and where the result can be off.
The equations
The page implements the NOAA Global Monitoring Laboratory solar calculator (a public-domain US government work): from the Julian century it derives the Sun’s geometric mean longitude and anomaly, the equation of centre, the apparent longitude, the obliquity of the ecliptic, the declination and the equation of time. Solar noon in minutes is 720 − 4·longitude − EoT + 60·UTC offset.
Rise, set and twilight
The hour angle at which the Sun’s centre reaches a zenith of 90.833° — the horizon plus 34′ of refraction and 16′ of solar radius — gives sunrise and sunset as solar noon ∓ 4·HA minutes, and the day length as 8·HA. Civil, nautical and astronomical twilight repeat the calculation for zeniths of 96°, 102° and 108°. When the cosine of the hour angle leaves [−1, 1] the Sun never rises or never sets that day.
Accuracy
About a minute for 1900–2100 at sea level with a flat horizon and standard refraction; altitude, mountains and unusual air change the real moment by minutes. The UTC offset is yours, including daylight saving on that date — no time-zone database is used. Nothing leaves the browser; the same four anonymous usage counts as the rest of the site apply.
SOURCES
- NOAA Global Monitoring Laboratory solar calculator equations (public domain): Julian century, obliquity, declination, equation of time; zenith 90.833° for rise/set, 96/102/108° twilight
Last reviewed 21 September 2026. How results are checked: How we verify.