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Daylight Hours Calculator

Date & Time

40.7128°, -74.0060° — UTC-05:00

About This Tool

Daylight Hours Calculator – Track Sunrise, Sunset, and Day Length

The amount of daylight a location receives changes every single day of the year, and knowing exactly how much is often more useful than knowing the precise clock time of sunrise or sunset. The Daylight Hours Calculator answers that question directly: pick a date and a location, and it returns the total time between sunrise and sunset, along with solar noon and the exact sunrise/sunset times.

Why daylight duration matters

Gardeners and farmers rely on day length to time planting and harvest schedules, since many crops are photoperiod-sensitive. Photographers use sunrise and sunset to plan golden hour and blue hour sessions. Solar panel installers estimate usable sunlight hours per day, and remote workers or travelers use daylight duration to plan outdoor activities around a destination's seasonal light. Because the tool works for any coordinates on Earth, it is equally useful for comparing a single city across the year or comparing two very different cities on the same day.

How the calculation works

The tool computes the sun's declination angle— how far the sun is north or south of the equator on a given date — and combines it with your location's latitude to solve the hour angle, the angular distance the sun travels between sunrise and solar noon. Daylight duration is then 2 × hour angle ÷ 15hours, since the sun moves 15° per hour. Solar noon itself is adjusted for your longitude's offset from your timezone's standard meridian and for the equation of time, a small seasonal correction that accounts for Earth's elliptical orbit and axial tilt.

Midnight sun and polar night

At latitudes above roughly 66.5° (the Arctic and Antarctic circles), the standard hour-angle formula can have no real solution — that's the mathematical signature of midnight sun (the sun never sets) or polar night (the sun never rises). The calculator detects this automatically and reports the special condition instead of an invalid numeric duration.

Try an extreme example
Select Longyearbyen, Svalbard and set the date to June 21st to see midnight sun in action, or December 21st to see polar night.

Comparing dates and tracking yearly trends

Beyond a single calculation, the tool includes a Compare Dates mode that reports the exact difference in daylight between any two dates at the same location — useful for seeing how much longer summer days are compared to winter. The Yearly Trend mode plots daylight duration for every day of a chosen year, automatically marking the longest day (summer solstice) and the shortest day (winter solstice) at that location.

Reading the results

Each calculation returns sunrise, sunset, solar noon (the moment the sun is highest in the sky, not always exactly 12:00 pm local time), and the total daylight duration formatted as hours and minutes. A day/night timeline visualizes the proportion of the 24-hour day spent in daylight versus darkness, and a badge shows how much the day length has changed compared with the previous day — a useful indicator of how quickly the seasons are turning at that latitude.

Accuracy

Results are typically accurate to within one to two minutes of the true solar event time. Small deviations can occur due to atmospheric refraction near the horizon, local elevation, or nearby terrain that blocks the direct view of sunrise or sunset — none of which are modeled by the astronomical formulas alone.

Frequently Asked Questions

Is the Daylight Hours Calculator free?

Yes, Daylight Hours Calculator is totally free :)

Can I use the Daylight Hours Calculator offline?

Yes, you can install the webapp as PWA.

Is it safe to use Daylight Hours Calculator?

Yes, any data related to Daylight Hours Calculator only stored in your browser (if storage required). You can simply clear browser cache to clear all the stored data. We do not store any data on server.

How does the Daylight Hours Calculator work?

It uses the sun's declination angle and hour-angle formulas (the same NOAA solar calculation approach used by professional almanacs) to find sunrise, sunset, and solar noon for any latitude, longitude, and date. Daylight duration is simply the time between sunrise and sunset.

Why does daylight duration change throughout the year?

Earth's axis is tilted about 23.44° relative to its orbit around the sun. As Earth orbits, each hemisphere tilts toward or away from the sun, changing the sun's angle in the sky and the length of time it stays above the horizon — creating shorter winter days and longer summer days.

What is 'midnight sun' and 'polar night'?

Near the Arctic and Antarctic circles, the sun can stay continuously above the horizon (midnight sun, common around the summer solstice) or continuously below it (polar night, around the winter solstice). When this happens the calculator reports the special condition instead of a sunrise/sunset time, since neither event occurs that day.

How accurate is the daylight duration this tool reports?

The underlying solar-position formulas are accurate to within roughly 1–2 minutes for most locations and dates. Local terrain, elevation, and atmospheric refraction can shift the exact moment the sun's disc crosses the horizon by a small amount, but the overall daylight length is highly reliable for planning purposes.

Can I compare daylight between two dates or two cities?

Yes. Comparison mode lets you calculate daylight duration for a second date (or a second location) and shows the exact difference, so you can see, for example, how much longer days are in June than in December, or how daylight differs between two cities on the same date.

What does the yearly daylight trend chart show?

It plots the daylight duration for every day of the selected year at your chosen location, making it easy to see the gradual rise and fall in day length and to spot the longest day (summer solstice), the shortest day (winter solstice), and the two days with roughly equal day and night (equinoxes).