Sunrise Sunset Calculator
Calculate date and time values locally with visible assumptions and copy-ready results.
Use calendar math with the assumption visible
Use it for planning outdoor work, photography, hikes, garden tasks, travel days, and rough daylight estimates without a weather API. Sunrise and sunset require latitude, longitude, date, solar declination, and hour angle, so this page is an estimate by design.
The calculator uses a simplified NOAA-style solar equation with latitude, longitude, date, declination, and hour angle to estimate sunrise and sunset. The Los Angeles sample gives a concrete offline daylight calculation without calling a weather or mapping API.
Limits and local processing
It is an offline estimate and does not adjust for elevation, mountains, buildings, refraction details, or official local observatory data. Coordinates and dates stay in the browser while the approximation runs. Use official local data when elevation, terrain, civil twilight, or legal sunrise definitions matter. The output is best treated as planning context for daylight, not a legal sunrise or sunset source.
Frequently Asked Questions
How does the sunrise sunset calculator work?
The calculator uses a simplified NOAA-style solar equation with latitude, longitude, date, declination, and hour angle to estimate sunrise and sunset.
When should I use this tool?
Use it for planning outdoor work, photography, hikes, garden tasks, travel days, and rough daylight estimates without a weather API.
What should I watch out for?
It is an offline estimate and does not adjust for elevation, mountains, buildings, refraction details, or official local observatory data.
Is this date tool private?
Yes. It runs entirely in your browser, so dates, schedules, and notes are not uploaded or stored.
More free browser utilities for planning, formatting, and technical cleanup.