Season
Shows the current season (summer, autumn, winter, spring) in the Southern or Northern Hemisphere for any date.
How are seasons defined?
Behind this sit the approximate astronomical dates of the solstices and equinoxes. In the Southern Hemisphere, summer begins on Dec 21, autumn on Mar 21, winter on Jun 21 and spring on Sep 23. The Northern Hemisphere shares the same dates, but the seasons flip.
The default hemisphere comes from your browser timezone (south for Brazilian zones), and you can switch it by hand whenever you need.
Nothing leaves your browser; the math runs locally.
What season is it?
Seasons kick off on dates that slide from one year to the next, and on top of that they're flipped between hemispheres. When Brazil gets summer, Europe is deep in winter. This tool tells you which season any date falls in, for whichever hemisphere you pick.
It points out whether we're in summer, autumn, winter or spring. The calculation starts from the equinoxes and solstices and takes the gap between the Southern and Northern hemispheres into account. Handy for planning a trip, getting a feel for a destination's climate on the far side of the world, or just clearing up when a given season begins.
Think of it as a quick reference on the seasons. The calculation runs in the browser, and once the page has loaded you don't even need internet.