What this calculator does
Estimate sunrise, sunset, solar noon, and day length from date, latitude, longitude, and UTC offset.
How it works
The calculator evaluates sunrise and sunset use the NOAA solar-position approximation with zenith 90.833°. Inputs are checked before calculation, and invalid values such as zero denominators or out-of-range selections produce a clear error instead of a misleading result.
Input query strings and outputs
Use an input name in this page’s URL as ?name=value, and join additional inputs with &. Portable shared links may instead use the compact ?ac= state parameter.
Input query strings
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?date=DateDate · Required · Default: 2026-09-01
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?latitude=Latitude (degrees)Number · Required · Default: 42.3601
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?longitude=Longitude (degrees; east positive)Number · Required · Default: -71.0589
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?utcOffset=UTC offset (hours)Number · Required · Default: -4
Outputs
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sunriseSunriseText · Primary output
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sunsetSunsetText
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solarNoonSolar noonText
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dayLengthDay lengthText
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statusSolar statusText
Inputs and results
The inputs are Date, Latitude (degrees), Longitude (degrees; east positive), UTC offset (hours). Results include Sunrise, Sunset, Solar noon, Day length, Solar status.
Important notes
Sunrise and sunset are estimates based on a standard solar model. Verify the UTC offset and daylight-saving status for the location.