Islamic Calendar

1st day of Ramadan 1441 AH: Friday, April 24, 2020 (Starting evening of Thursday, Apr 23)
Last day of Ramadan 1441 AH: Saturday, May 23, 2020
Eidul-Fitr 1441 AH: Sunday, May 24, 2020
Eidul-Adha 1441 AH: Friday, July 31, 2020 (The day following the day of ‘Arafah’)

Reference:
https://moonsighting.com/important.html
http://moonsighting.com/ramadan-eid.html

The Islamic Calendar with Gregorian Dates

https://www.moonsighting.com/2020fcna.html

On Friday, Oct 4, 2019, Members of Islamic Society of Belleville expressed their preference on the selection of Islamic (Hijri) Calendar. Majority of brothers and sisters expressed willingness to adapt Scientific Calendar for Important Islamic dates.

Astronomical method of calculating lunar cycles and Hijri dates has been adopted by the ‘Fiqh Council of North America‘ and major mosques and Islamic Centers in North America.
More information on the calculations: https://www.moonsighting.com/