Pick a date, or hit one of the usual suspects.
No — this counts the sleeps: if the event is tomorrow, it’s 1 day away; if it’s today, it’s 0 and the tool says so. The preset buttons always jump to the next occurrence, so on December 26 “Christmas” means next year’s.
The US one — fourth Thursday of November. Canada’s (second Monday of October) is easy to pick by hand.
Entirely in your browser. Dates you type are never sent anywhere — there is no server doing the math, no analytics watching you do it.