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Daylight Calculator
Calculate sunrise, sunset, daylight hours, and twilight durations for any latitude and day of the year using solar position equations.
Daylight Hours⧉
11h 59m
Time between sunrise and sunset
Sunrise⧉
03:08
Local time of geometric sunrise
Sunset⧉
15:08
Local time of geometric sunset
Solar Noon⧉
09:08
When the sun is at its highest point
Civil Twilight⧉
68 min
Additional light from −0° to −6° (can read outdoors)
Solar Declination⧉
-0.07°
Tilt of Earth toward sun on this date
Equation of Time⧉
-7.9 min
Difference between solar time and clock time
Night Hours⧉
10.9 h
True darkness after civil twilight ends
Day Composition
Daylight
12.0h
Civil Tw.
1.1h
Nautical
1.1h
Astro.
1.2h
Night
10.9h
Seasonal Daylight Table
| Date | Day | Daylight | Decl. (°) |
|---|---|---|---|
| Jan 1 | 1 | 8.7h | -22.9 |
| Feb 1 | 32 | 9.6h | -17.4 |
| Mar 1 | 60 | 10.9h | -8.0 |
| Equinox | 80 | 12.0h | -0.1 |
| Apr 1 | 91 | 12.6h | 4.3 |
| May 1 | 121 | 14.1h | 15.0 |
| Jun 1 | 152 | 15.2h | 21.9 |
| Solstice | 172 | 15.4h | 23.3 |
| Jul 1 | 182 | 15.4h | 23.0 |
| Aug 1 | 213 | 14.6h | 18.3 |
| Sep 1 | 244 | 13.2h | 8.7 |
| Oct 1 | 274 | 11.6h | -2.9 |
| Nov 1 | 305 | 10.0h | -14.3 |
| Dec 1 | 335 | 8.9h | -21.6 |
| Solstice | 356 | 8.6h | -23.2 |
Planning notes, formulas, and examples
About the Daylight Calculator
The amount of daylight at any location on Earth depends on two key factors: latitude and the time of year. Near the equinoxes, everywhere on Earth receives approximately 12 hours of daylight. But as the seasons progress, higher latitudes experience dramatic changes—from nearly 24 hours of light in summer to almost total darkness in winter polar regions.
This daylight calculator uses precise solar position algorithms to compute sunrise, sunset, daylight duration, and twilight periods for any latitude and any day of the year. It accounts for atmospheric refraction, observer elevation, and the equation of time to produce times that closely track published almanac data.
Beyond simple sunrise and sunset times, the calculator breaks down the full day into its components: direct sunlight, civil twilight (when outdoor activities are still possible), nautical twilight, astronomical twilight, and true night. This complete picture is invaluable for photography planning, outdoor activities, astronomical observation, and understanding our planet's orbital mechanics.
When This Page Helps
Whether you're planning photography golden hours, agricultural activities, outdoor events, or just curious about seasonal light patterns, it gives precise daylight information for any location and date without needing specialized astronomy software.
How to Use the Inputs
- Enter your latitude in degrees (positive for Northern Hemisphere, negative for Southern).
- Input the day of the year (1–365) or use a preset for key dates like solstices and equinoxes.
- Set your elevation above sea level for more precise sunrise/sunset times.
- Choose the twilight type to see extended light availability.
- Enter your UTC offset to get times in your local timezone.
- Review the day composition bar chart for a visual breakdown of light and darkness.
- Check the seasonal table to see how daylight varies throughout the year at your latitude.
Formula used
Solar declination: δ = 0.006918 − 0.399912cos(γ) + 0.070257sin(γ) − ...
Hour angle: cos(H) = [cos(90°) − sin(φ)sin(δ)] / [cos(φ)cos(δ)]
Daylight hours = 2H / 15
Equation of Time: EoT = 229.18 × [0.000075 + 0.001868cos(γ) − 0.032077sin(γ) − ...]
Where γ = (2π/365)(day − 1) and φ = latitude.Example Calculation
Result: 15h 37m daylight, sunrise 04:32, sunset 20:09
At 45°N latitude on the summer solstice (day 172), there are about 15 hours and 37 minutes of daylight, with sunrise around 4:32 AM and sunset around 8:09 PM solar time.
Tips & Best Practices
- The day of year for key dates: March equinox ≈ 80, June solstice ≈ 172, September equinox ≈ 266, December solstice ≈ 356.
- Southern hemisphere latitudes should be entered as negative values.
- Golden hour for photography occurs roughly 30 minutes after sunrise and before sunset.
- The longest twilight periods occur at high latitudes around the solstices.
- At the equator, daylight is nearly constant at ~12 hours year-round with very brief twilights.
When To Use This Calculator
Calculate sunrise, sunset, daylight hours, and twilight durations for any latitude and day of the year using solar position equations. Use it when you need a repeatable calculation in the physics / general category and want the setup, result, and supporting values kept together. This is especially helpful when small input changes, unit choices, or rounding decisions can change the final number.
How To Check The Result
Start by confirming that the inputs match the formula shown on the page. Then compare the main output with the worked example and any secondary values shown by the calculator. If the result will be used in another calculation, keep extra precision until the final step and record the assumptions beside the number.
Practical Notes
Treat the result as a calculation aid rather than a substitute for context. For schoolwork, include the formula and substitution steps. For planning, technical, financial, or health-related decisions, verify important numbers against primary records, current rules, or a qualified professional before acting on them.
Sources & Methodology
Last updated:
Frequently Asked Questions
This calculator uses geometric sunrise/sunset with standard atmospheric refraction. Local terrain, actual atmospheric conditions, and precise longitude within a timezone can cause differences of 1–3 minutes.
Civil twilight is the period when the sun is between 0° and 6° below the horizon. There is enough light to see objects clearly outdoors without artificial light. It lasts about 30 minutes at mid-latitudes.
When the solar declination exceeds the co-latitude (90° − latitude), the sun never dips below the horizon. This occurs inside the Arctic/Antarctic circles during their respective summers.
Higher elevation allows you to see the sun earlier because your geometric horizon is lower. Each 100m of elevation gains roughly 1 minute of extra daylight.
The equation of time accounts for Earth's elliptical orbit and axial tilt, which cause solar noon to drift by up to ±16 minutes from mean solar time throughout the year.
No, results are in solar time adjusted by your UTC offset. Add 1 hour during daylight saving time periods.
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