Date maths
Working days between two dates, and deadlines that skip weekends.
Nothing you enter is sent anywhere
Calendar days
1
Working days
1
Weekend days
0
Holidays
0
Both endpoints are counted, which is what people mean by "how many days do I have". Subtract one if you want the gap between them instead.
Public holidays
One date per line as YYYY-MM-DD. No holiday list is built in on purpose. Sri Lanka’s Poya days follow the lunar calendar and shift every year, and a wrong date baked into a tool is worse than no date at all. Take the current gazette from the Ministry of Public Administration and paste it here.