Every figure has a published source
Nothing on this site is estimated from memory or from another calculator's output. Solar positions use the standard low-precision solar equations published by NOAA's Global Monitoring Laboratory, and the lunar phase and phase-fraction relationships use the published synodic-month material. Each tool page ends with a Sources and standards section naming the references it implements.
A reference is only cited if the page itself actually supports the statement being cited. If a source cannot be opened and read, it is not used as a citation, and no figure in this site rests on a reference we have not seen.
Worked examples are run, not typed
The worked examples in every guide were produced by the same engine the live calculator uses, not written by hand. That is why the numbers in the text and the numbers on the page agree. Where an example depends on a table — conductor sizes, conduit areas, city coordinates — the table itself is the one the calculator uses, so the two cannot drift apart.
How time zones and daylight saving are handled
Times are shown in civil time for the time zone you select, and daylight saving is applied from that zone's own rules rather than from a fixed offset. Dates are therefore calculated individually, so a place either side of a daylight-saving boundary is right on both sides of it, including on the transition day itself. Where a city page prints a fixed standard-time figure, the page says so and states which dates the offset changes.
What a city page has to contain
This is the part of the policy that matters most for the city pages, and it is a floor rather than a goal. A city page is accepted only if it contains material that is specific to that place: the coordinates and time zone actually used, the local circumstances that change the answer — horizon, terrain, the date on which the clock changes — and the differences from a neighbouring city that people actually ask about. Swapping a city name into a template is not a city page, and pages like that are not published.
Every city page is also reviewed for whether the page it links to actually helps: a question about the moon in Madrid that only leads back to a generic calculator is a dead end, and dead ends are not shipped.
What this site does not do
- No figures that cannot be traced to a published method.
- No citations to sources that cannot be opened and read in full.
- No keyword padding, no placeholder sections, and no pages published only to occupy a search result.
- No invented authors, credentials or affiliations. The site is written and maintained by one independent developer, and it is described that way wherever it is described.
- No claims about rankings, traffic or what a search engine will do. Those are not ours to promise.
- No affiliate links presented as editorial recommendations. Where a product is listed, it is because the job needs it.
Dating and updates
Each page carries the date its figures were last checked. When a formula, table or engine changes, the affected pages are re-checked, the date is updated and the change is reflected in the site's sitemap. Corrections are made the same way: the page is fixed, the date moves, and if the error was visible to readers, the correction is recorded on the contact page trail rather than quietly edited away.
Figures and references last reviewed: 28 October 2026.