Upcoming:

• 29th Oct 2016 : CodeChef Lunchtime
• 5th Nov 2016 : COCI Contest #2
• 20th Nov 2016 : ZIO, ZCO (India)
• 26th Nov 2016 : COCI Contest #3
• 26st Nov 2016 : CodeChef Lunchtime
• Dec 2016 : USACO Contest #1
• 17th Dec 2016 : COCI Contest #4
• 31st Dec 2016 : CodeChef Lunchtime
• Jan 2017 : USACO Contest #2
• 8th Jan 2017 : INOI (India)
• 14th Jan 2017 : COCI Contest #5
• Feb 2017 : USACO Contest #3
• 4th Feb 2017 : COCI Contest #6
• 4th Mar 2017 : COCI Contest #7
• Apr 2017 : USACO Open
• May 2017 : APIO
• July 2017 : CEOI

Past:

• 15th Oct 2016 : COCI Contest #1

Website links

• Croatian Open Competition in Informatics
• USA Computing Olympiad
• Indian Computing Olympiad (ZIO, ZCO, INOI)
• Asia-Pacific Informatics Olympiad (coming soon)
• Central European Olympiad in Informatics
• CodeChef contests

If you know of other IOI-style contests, do let us know by adding a reply