The holiday of Shavuot falls on the Hebrew calendar dates of Sivan 6–7. Here are the coinciding secular dates for the upcoming years:
2016: June 11–13
2017: May 30–June 1
Note: The Jewish calendar date begins at sundown of the night beforehand. Thus all holiday observances begin at sundown on the secular dates listed, with the following day being the first full day of the holiday. Jewish calendar dates conclude at nightfall.