Daylight Hours Calculator
Calculate sunrise, sunset, and total daylight for any location and date
How to Use This Tool
Enter the latitude and longitude of your location, or search for your city’s coordinates online to find these values quickly. Select your target date using the date picker, then choose your preferred result format and any daylight saving time adjustments for your region. Click Calculate to view your results, or Reset to clear all inputs and start over.
All fields are required for accurate calculations. Latitude ranges from -90 (South Pole) to 90 (North Pole), and longitude ranges from -180 (West) to 180 (East).
Formula and Logic
This calculator uses a simplified solar position algorithm adjusted for the equation of time to improve accuracy for everyday use. The core calculation steps are:
- Calculate the day of the year from your selected date to determine the sun’s position relative to Earth.
- Compute solar declination (the angle of the sun above or below the equator) using the day of the year.
- Calculate the hour angle (the sun’s angular distance from solar noon) based on your latitude and the solar declination.
- Derive sunrise and sunset times by adjusting solar noon for your longitude, the hour angle, and the equation of time.
- Apply daylight saving time adjustments to convert results to your local clock time.
Total daylight hours are calculated as the time difference between sunset and sunrise. Results are approximate and may vary slightly from official astronomical data due to local terrain, atmospheric conditions, and unaccounted minor orbital variations.
Practical Notes
For home cooks and gardeners: Use this tool to plan outdoor cooking, garden watering, or planting schedules around available sunlight. South-facing gardens receive more direct light, so adjust your latitude input if calculating for a specific microclimate.
For daily planners: Align outdoor exercise, commute timing, or evening routines with natural light to reduce reliance on artificial lighting. Note that daylight hours shift by ~2 minutes per day near the equinoxes, and up to ~5 minutes per day near the solstices.
Daylight saving time rules vary by region and year—double-check your local DST schedule if selecting an adjustment. Coastal locations may experience slightly different twilight times than inland areas due to horizon elevation differences.
Why This Tool Is Useful
Unlike generic sunrise/sunset apps, this tool lets you calculate daylight hours for any past or future date, making it ideal for long-term planning like vacation scheduling, seasonal home projects, or agricultural prep work.
It’s fully private: no location data is sent to external servers, so you can calculate daylight hours for remote or sensitive locations without privacy concerns. The detailed breakdown includes solar noon and multiple format options to fit your workflow.
Frequently Asked Questions
Why do my results differ from local sunrise/sunset times?
Small discrepancies may come from the equation of time adjustment, local terrain (mountains blocking the sun), or atmospheric refraction. For most everyday planning, these differences are negligible.
Can I use this tool for locations near the poles?
Yes, but note that polar regions may experience 24-hour daylight (midnight sun) or darkness (polar night) during solstices. The calculator will return 24 hours or 0 hours of daylight for these edge cases.
How do I find my latitude and longitude?
Search for your city plus “latitude and longitude” on any search engine, or use your smartphone’s map app to drop a pin and view coordinates. Most consumer GPS devices also display these values.
Additional Guidance
For photographers: Golden hour occurs ~1 hour after sunrise and ~1 hour before sunset—use the calculated sunrise/sunset times to plan shoots. For energy savers: Aligning laundry or dishwashing with daylight hours can reduce evening electricity use.
If calculating for a trip, pre-load dates for your destination to pack appropriate clothing and plan activities. Always verify critical timing (like flight schedules) with official sources, as this tool is for general planning only.