Which side of the train, bus, plane or ferry gets the sun on your trip, and which window your landmark is behind. Two cities, a departure time. Free.
All the free tools
Every tool fastast serves, each on its own page. No account, no e-mail, nothing stored — open one, use it, close the tab.
Every tool here does one thing, on one page, and asks nothing of you: no account, no e-mail address, no cookie banner to dismiss before you can work. Type what you need, read the answer, close the tab. Nothing you enter is kept.
Each tool has its own address, so a link to one is a link to that tool alone. The list below is the whole set, and the search box filters it by name or by what a tool does.
What colour the clear sky is over any city, right now or at a chosen moment: the gradient, hex codes and CSS, the light of the hour and when it changes.
Every retrograde period of a year, Mercury through Pluto, station to station with dates and durations. Download the table or subscribe as a calendar.
When the Sun or Moon lines up with a street, a bridge or a ridge from where you stand: give a bearing or a landmark, get twelve months of dates.
Equinox and solstice dates for any year, to the minute in UTC, with cross-quarter days, perihelion, aphelion and your own longest day. Free.
Which nights of the next year the Milky Way core is visible from your location: dark sky, no Moon, core high enough, grouped into runs. Free.
Moon phase calendar for your city: every night's phase, illumination, moonrise and moonset, distance and size, and how big it is on your lens.