Chinese Almanac曆 · the day, dated
Set it to your chart
Give a birth date and the days below are marked against your own sign — the days that clash with it, the days that meet it, and your own. Add a time and a place and you also get your day pillar and your hour animal.
None of it leaves this phone. There is no account and nothing is sent anywhere. Clearing your browser clears it.
Clock time where you were born. Leave it blank if you are not sure — a guessed hour is worse than none.
Only the longitude is used, to turn clock time into sun time. Without it an hour given near a boundary can land in the wrong one.