Find daylight, golden hour, and twilight times for any location
Default: San Francisco, CA
| Day | Sunrise | Sunset | Daylight | Solar Noon |
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This calculator uses the NOAA (National Oceanic and Atmospheric Administration) solar position algorithm — the same formula used by government weather services worldwide. The calculation is based on three key astronomical parameters:
Solar Declination — the angle of the sun relative to Earth's equatorial plane. It varies from +23.45° (summer solstice in the Northern Hemisphere) to −23.45° (winter solstice). At the equinoxes, declination is 0°.
Solar Zenith Angle — the angle between the sun and the vertical (directly overhead). Sunrise and sunset are defined by a specific zenith angle: 90.833° (accounting for atmospheric refraction and the solar disk's angular radius). Civil twilight uses 96°, nautical 102°, and astronomical 108°.
Equation of Time — the discrepancy between apparent solar time (sundial time) and mean solar time (clock time), caused by Earth's elliptical orbit and axial tilt. This difference can be up to ±16 minutes, and the NOAA formula accounts for it precisely.
Golden hour — the period when the sun is between 6° above and 4° below the horizon — produces soft, warm, directional light with long shadows. Colors appear richer and skin tones are flattering. Blue hour (civil twilight, when the sun is 4-6° below the horizon) creates cool, saturated blue tones popular for cityscapes. For photographers, planning around these times is essential: the exact duration of golden hour varies from about 20 minutes near the equator to over 90 minutes at high latitudes during summer.
Click "📍 My Location" to use your device's GPS, or enter latitude and longitude manually. The calculator shows today's full sun schedule including golden hour and twilight times, calculated with the NOAA formula.
Golden hour is the period shortly after sunrise and before sunset when the sun is low, producing warm, diffused light. It's prized by photographers because the light is softer (fewer harsh shadows), warmer in color temperature, and creates a natural sense of depth. Morning golden hour lasts roughly from sunrise to 60 minutes after; evening golden hour is the 60 minutes before sunset.
Civil twilight (sun 0-6° below horizon): enough light to see clearly, only the brightest stars visible. Nautical twilight (6-12°): horizon still discernible for marine navigation, most stars visible. Astronomical twilight (12-18°): sky is dark for astronomy, but the faintest objects require the sun to be below 18°.
Day length changes because Earth's axis is tilted 23.5° relative to its orbit. During summer in your hemisphere, your location is tilted toward the sun, resulting in longer days. During winter, you're tilted away, producing shorter days. At the equator, day length is nearly constant (~12 hours) year-round.