About DateAlmanac

Sunrise, sunset and twilight use the NOAA solar position algorithm, evaluated from each place’s own coordinates. The result is checked against times published by the US Naval Observatory: mean error 0.59 minutes, 93 of 100 values within one minute, worst case 3 minutes at 61°N. The error grows toward the poles, because the sun meets the horizon at a shallower angle there, so a given error in altitude moves the time further.

Moonrise, moonset and phase follow Meeus, Astronomical Algorithms, chapter 47, checked the same way against 100 USNO values: every one of 288 times within a minute, mean 0.11.

Time zones and daylight saving come from the IANA time zone database as the operating system ships it, read through the runtime’s own internationalisation data. Clock-change dates are found by searching for the moment the offset actually changes, so they follow the law rather than a copy of it.

US federal holidays are the five rules in 5 U.S.C. §6103, expressed as rules rather than stored dates. Religious dates resolve through the Hebrew and Umm al-Qura calendars. Islamic dates are a convention rather than a fact, and local sighting can differ by a day; the pages say so.

Cities and coordinates come from two public-domain US Census sources — the 2025 Gazetteer place file and the 2024 Population Estimates programme — with 2020 Census counts filling in the Census Designated Places the estimates programme leaves out.

• It does not scrape other date or time-zone sites for data or wording.
• It has no accounts, no sign-in, no forms and no newsletter, so there is nothing to submit and nothing stored about you beyond the analytics described in the privacy policy.
• It does not publish Hindu festival dates. Diwali and Holi are lunisolar and vary by region and by panchang, and the calendar data needed to compute them properly is not something this site has. An absence with a reason is better than a guess.
• It does not give legal, financial, medical or religious advice, and the dates here should not be the only source for anything that matters. See the terms.

Calendars, holiday dates and religious calendars cover 2026 to 2031. Day counts run to 400 days either side of today. Sunrise and sunset are available for 2,500 US places.

Anything described as “today” is computed in US Eastern Time and every such page names that basis, because the United States spans six zones and a reader in California at 9pm is already on New York’s tomorrow.

This page was last reviewed on September 29, 2026.

DateAlmanac is published by REN Technology Limited, registered in England and Wales under company number 13694812, based in Manchester, United Kingdom. It is a small independent operation, not a data business: it sells nothing, carries no advertising and has nothing to sign up for.

If a figure here looks wrong, that is worth knowing about — please report it, and say which page and what you expected.