View source for International Olympiad in Informatics

{{Short description|Annual programming competition}}
{{Primary sources|date=August 2017}}
[[File:InternationalOlympiadInInformatics.png|thumb|right|The logo of the International Olympiad in Informatics]]

The '''International Olympiad in [[Informatics]]''' ('''IOI''') is an annual [[competitive programming]] competition and one of the [[International Science Olympiads]] [[Student competition|for secondary school students]]. The first IOI was held in 1989 in [[Pravetz]], Bulgaria.

Each country sends a team of up to four students, plus one team leader, one deputy leader, and guests. Students in each country are selected for their country's team through [[#Feeder competitions|national computing contests]]. Students at the IOI compete on an individual basis. There is no official team ranking.

The contest consists of two days of solving six complicated [[algorithm]]ic tasks by writing computer programs in [[C++]].<ref name="Robson">{{cite news |last=Robson |first=Frank |date=10 August 2013 |title=Numbers game |url=http://www.smh.com.au/technology/technology-news/numbers-game-20130805-2r9yi.html |access-date=17 August 2013 |newspaper=[[The Sydney Morning Herald]]}}</ref><ref>{{Cite web |title=Contest Rules |url=https://www.ioi2024.eg/contest-rules |access-date=2024-10-15 |website=IOI 2024 Egypt |language=en}}</ref> All task materials are published on each year's contest website soon after the competition ends.

== Competition structure and participation ==
[[File:IOI 2006 competition room.png|thumb|The competition room at the IOI 2006]]
{{multiple image
| footer = A bronze medal from IOI 2006 in Mexico
 | align     = right
| image1   = IOI 2006 bronze medal (front).jpg
| width1   = 150
| alt1     =
| caption1 = Front
| image2   = IOI 2006 bronze medal (back).jpg
| width2   = 150
| alt2     =
| caption2 = Back
}}
[[File:IOI Zagreb 1.JPG|thumb|In front of the competition room at the IOI 2007]]

On each of the two competition days, the competitors are typically given three problems which they have to solve in five hours. Each student works on their own to solve the problems with no outside help, specifically no communication with other contestants, books, web access, etc. Contestants are typically allowed to bring non-programable wired keyboards and mice.<ref>{{cite web |title=Competition Equipment |url=https://www.ioi2024.eg/competition-equipment |website=IOI 2024 Egypt |publisher=Arab Academy |access-date=29 July 2024}}</ref> Usually to solve a task the contestant has to write a computer program (in [[C++]]) and submit it before the five-hour competition time ends. The program is graded based on secret test data. Since IOI 2010, tasks are divided into subtasks with graduated difficulty, and points are awarded only when all tests for a particular subtask yield correct results, within specific time and memory limits. In some cases, the contestant's program has to interact with a secret computer library, which allows problems where the input is not fixed, but depends on the program's actions – for example in game problems (a.k.a interactive problems). Another type of problem has the inputs publicly available, for these, the contestants have to submit an output file instead of a program, and it is up to them whether they obtain the output files by writing a program (possibly exploiting special characteristics of the input), or by hand, or by a combination of these means. Pascal has been removed as an available programming language as of 2019.<ref name="minutes16">{{cite web|title=Minutes of the Meetings held in Kazan, Russian Federation|url=https://www.ioinformatics.org/files/ioi2016minutes.pdf|website=ioinformatics.org|publisher=General Assembly of International Olympiad in Informatics|pages=7, 11|date=19 August 2016}}</ref><sup>:11</sup>

IOI 2010 for the first time had a live web scoreboard with real-time provisional results.  Submissions will be scored as soon as possible during the contest, and the results posted. Contestants will be aware of their scores, but not others', and may resubmit to improve their scores. Starting from 2012, IOI has been using the Contest Management System (CMS) for developing and monitoring the contest.<ref>{{cite web |title=IOI 2010 Waterloo |url=https://www.ioi2010.org/ |website=IOI 2010 Waterloo |publisher=University of Waterloo |access-date=29 July 2024}}</ref>

The scores from the two competition days and all problems are summed up separately for each contestant. Medals are awarded depending on their relative total score. The top 50% of the contestants are awarded medals, such that the relative number of gold : silver : bronze : no medal is approximately 1:2:3:6 (thus 1/12 of the contestants get a gold medal).

Prior to IOI 2010, students who did not receive medals did not have their scores published, although the scores of students who did not receive medals are still not available in the official results, they are known from the live web scoreboard. In IOI 2012 the top 3 nations ranked by aggregate score (Russia, China and USA) were subsequently awarded during the closing ceremony.

Analysis of female performance shows 77.9% of women obtain no medal, while 49.2% of men obtain no medal. "The average female participation was 4.4% in 1989–1994 and 2.2% in 1996–2014." It also suggests much higher participation of women on the national level, claiming sometimes double-digit percentages in total participation on the first stage.<ref>{{cite journal|last1=Maggiolo|first1=Stefano|title=An Update on the Female Presence at the IOI|journal=Olympiads in Informatics|volume=9, 127–137|issue=2015|pages=127–137|doi=10.15388/ioi.2015.10|url=http://ioinformatics.org/oi/pdf/v9_2015_127_137.pdf|access-date=13 July 2017|publisher=ioinformatics.org|location=London, U.K.|year=2015|doi-access=free}}</ref> President of the IOI (2011-2014), Richard Forster, says the competition has difficulty attracting women and that in spite of trying to solve it, "none of us have hit on quite what the problem is, let alone the solution."<ref name="Robson" /> The European Girls’ Olympiad in Informatics ([[EGOI]]), which was first held in 2021 was started with the goal to increscent female participants at IOI and other Informatics Olympiads.<ref>{{cite web |title=European Girls’ Olympiad in Informatics |url=https://egoi.org/ |website=European Girls’ Olympiad in Informatics |publisher=European Girls’ Olympiad in Informatics}}</ref>

In IOI 2017 held in Iran, due to not being able to participate in Iran, the Israeli students participated in an offsite competition organized by IOI in Russia.<ref name="minutes16" /><sup>:11</sup> Due to visa issues, the full USA team was unable to attend, although one contestant Zhezheng Luo<ref>{{cite web|url=http://stats.ioinformatics.org/people/6410|title=Zhezheng Luo|website=stats.ioinformatics.org}}</ref> was able to attend by traveling with the Chinese team<ref>{{cite web|last1=Simões|first1=Gabriel|title=IOI 2017, first round - Codeforces|url=http://codeforces.com/blog/entry/53550#comment-375744|website=Codeforces|access-date=4 August 2017|date=31 July 2017|quote=There is really only one USA contestant on site, it looks like he came with the Chinese team (straight from China).}}</ref> and winning gold medal and 3rd place in standings.<ref name="standings2017">{{cite web|url=http://stats.ioinformatics.org/results/2017|title=IOI 2017: Results|website=stats.ioinformatics.org}}</ref>

In IOI 2019 held in Azerbaijan, the Armenia team did not participate due to the [[Karabakh conflict|dispute between the two countries]], despite the guarantees provided<ref>{{Cite web|title=General Assembly Minutes of the Meetings held in Almaty, Kazakhstan 26 July – 2 August, 2015|url=https://ioinformatics.org/files/ioi2015minutes.pdf}}</ref> and official invitation letter sent by the host Azerbaijan.

Due to the [[COVID-19 pandemic]], both the IOI 2020 and IOI 2021, originally scheduled to be hosted by [[Singapore]], were held as online contests. The IOI 2022, hosted by [[Indonesia]], was held as a hybrid event, with around 25% of the contestants participating online.<ref>{{cite web|url=https://ioi2022.id/number-of-participants/|title=Number of Participants|website=ioi2022.id}}</ref>

In response to the invasion of Ukraine, students from Russia and Belarus can only participate as individuals under the IOI flag but not as national delegations starting from IOI 2022, and they would only participate online for IOI 2022, but they may return on-site from IOI 2023 onwards.<ref>{{cite web|url=https://ioinformatics.org/news/ioi-response-to-invasion-of-ukraine/40|title=IOI response to invasion of Ukraine|website= International Olympiad in Informatics| date=March 12, 2022|access-date=September 28, 2024}}</ref>

In response to the conflict and humanitarian crisis in Gaza, students from Israel can only participate as individuals under the IOI flag but not as a national delegation from IOI 2025 onwards. Over two thirds of the delegations voted in favour of the sanction in the IOI General Assembly.<ref>{{cite web|url=https://ioinformatics.org/news/ioi-response-to-the-conflict-in-gaza/52|title=IOI response to the conflict in Gaza|website= International Olympiad in Informatics| date=September 24, 2024|access-date=September 28, 2024}}</ref>

{{Clr}}

== Members ==
{{div col|colwidth=15em}}
*{{flag|Albania}}
*{{flag|Algeria}}
*{{flag|Argentina}}
*{{flag|Armenia}}
*{{flag|Australia}}
*{{flag|Austria}}
*{{flag|Azerbaijan}}
*{{flag|Bangladesh}}
*{{flag|Belarus}}
*{{flag|Belgium}}
*{{flag|Bolivia}}
*{{flag|Bosnia and Herzegovina}}
*{{flag|Brazil}}
*{{flag|Bulgaria}}
*{{flag|Canada}}
*{{flag|Chile}}
*{{flag|China}}
*{{flag|Colombia}}
*{{flag|Croatia}}
*{{flag|Cuba}}
*{{flag|Cyprus}}
*{{flag|Czech Republic}}
*{{flag|Denmark}}
*{{flag|Dominican Republic}}
*{{flag|Ecuador}}
*{{flag|Egypt}}
*{{flag|El Salvador}}
*{{flag|Estonia}}
*{{flag|Finland}}
*{{flag|France}}
*{{flag|Georgia}}
*{{flag|Germany}}
*{{flag|Greece}}
*{{flag|Hong Kong}}
*{{flag|Hungary}}
*{{flag|Iceland}}
*{{flag|India}}
*{{flag|Indonesia}}
*{{flag|Iran}}
*{{flag|Ireland}}
*{{flag|Israel}}
*{{flag|Italy}}
*{{flag|Japan}}
*{{flag|Jordan}}
*{{flag|Kazakhstan}}
*{{flag|Kyrgyzstan}}
*{{flag|Latvia}}
*{{flag|Libya}}
*{{flag|Lithuania}}
*{{flag|Luxembourg}}
*{{flag|Macau}}
*{{flag|Malaysia}}
*{{flag|Mexico}}
*{{flag|Moldova}}
*{{flag|Mongolia}}
*{{flag|Montenegro}}
*{{flag|Morocco}}
*{{flag|Netherlands}}
*{{flag|New Zealand}}
*{{flag|Nigeria}}
*{{flag|North Macedonia}}
*{{flag|Norway}}
*{{flag|Pakistan}}
*{{flag|Palestine}}
*{{flag|Peru}}
*{{flag|Philippines}}
*{{flag|Poland}}
*{{flag|Portugal}}
*{{flag|Romania}}
*{{flag|Russia}}
*{{flag|Rwanda}}
*{{flag|Saudi Arabia}}
*{{flag|Serbia}}
*{{flag|Singapore}}
*{{flag|Slovakia}}
*{{flag|Slovenia}}
*{{flag|South Africa}}
*{{flag|South Korea}}
*{{flag|Spain}}
*{{flag|Sri Lanka}}
*{{flag|Sweden}}
*{{flag|Switzerland}}
*{{flag|Syria}}
*{{flag|Taiwan}}
*{{flag|Tajikistan}}
*{{flag|Thailand}}
*{{flag|Tunisia}}
*{{flag|Turkey}}
*{{flag|Turkmenistan}}
*{{flag|Ukraine}}
*{{flag|United Kingdom}}
*{{flag|United States}}
*{{flag|Uzbekistan}}
*{{flag|Venezuela}}
*{{flag|Vietnam}}
{{div col end}}

=== Former members ===
{{div col|colwidth=15em}}
*{{flag|Gabon}}
*{{flag|Ghana}}
*{{flag|Kuwait}}
*{{flag|Madagascar}}
*{{flag|Malta}}
*{{flag|Mauritius}}
*{{flag|Mozambique}}
*{{flag|Sudan}}
*{{flag|Trinidad and Tobago}}
*{{flag|United Arab Emirates}}
*{{flag|Zimbabwe}}
{{div col end}}

== Summary ==
{| class="wikitable"
|-
! Number !! Year !! Dates !! Host country !! Host city !! Results !! Website 
|-
|1 || 1989 || May 16–19 || {{flagicon|Bulgaria|1971}} [[People's Republic of Bulgaria|Bulgaria]] || [[Pravets|Pravetz]] || <ref>{{cite web|url=https://stats.ioinformatics.org/results/1989|title=IOI 1989 Results}}</ref> ||
|-
| 2 || 1990 || July 15–21 || {{flagicon|Byelorussian SSR}} [[Belarusian SSR|Belarus]], [[Soviet Union]] || [[Minsk]] || <ref>{{cite web|url=https://stats.ioinformatics.org/results/1990|title=IOI 1990 Results}}</ref> ||
|-
| 3 || 1991 || May 19–25 || {{flagicon|Greece}} [[Greece]] || [[Athens]] || <ref>{{cite web|url=https://stats.ioinformatics.org/results/1991|title=IOI 1991 Results}}</ref> ||
|-
| 4 || 1992 || July 11–21 || {{flagicon|DEU}} [[Germany]] || [[Bonn]] || <ref>{{cite web|url=https://stats.ioinformatics.org/results/1992|title=IOI 1992 Results}}</ref>||
|-
| 5 || 1993 || October 16–25 || {{flagicon|ARG}} [[Argentina]] || [[Mendoza, Argentina|Mendoza]] || <ref>{{cite web|url=https://stats.ioinformatics.org/results/1993|title=IOI 1993 Results}}</ref> || <ref>{{cite web|url=http://www.ioi.org.ar/mendoza/|title=IOI 1993 Website|website=ioi1993|access-date=2024-03-07|archive-date=1999-02-24|archive-url=https://web.archive.org/web/19990224113008/http://www.ioi.org.ar/mendoza/|url-status=dead}}</ref>
|-
|6 || 1994 || July 3–10 || {{flagicon|Sweden}} [[Sweden]] || [[Haninge]]  || <ref>{{cite web|url=https://stats.ioinformatics.org/results/1994|title=IOI 1994 Results}}</ref> || <ref>{{cite web|url=http://www.haninge.kth.se/IOI/ioi.html|title=IOI 1994 Website|website=ioi1994|access-date=2024-03-07|archive-date=1997-01-02|archive-url=https://web.archive.org/web/19970102155956/http://www.haninge.kth.se/IOI/ioi.html|url-status=bot: unknown}}</ref>
|-
| 7 || 1995 || June 26 – July 3 || {{flagicon|NED}} [[Netherlands]] || [[Eindhoven]] || <ref>{{cite web|url=https://stats.ioinformatics.org/results/1995|title=IOI 1995 Results}}</ref> ||
|-
| 8 || 1996 || July 25 – August 2 || {{flagicon|Hungary}} [[Hungary]] || [[Veszprém]] || <ref>{{cite web|url=https://stats.ioinformatics.org/results/1996|title=IOI 1996 Results}}</ref> ||
|-
| 9 || 1997 || November 30 – December 7 || {{flagicon|RSA}} [[South Africa]] || [[Cape Town]] || <ref>{{cite web|url=https://stats.ioinformatics.org/results/1997|title=IOI 1997 Results}}</ref> ||
|-
| 10 || 1998 || September 5–12 || {{flagicon|Portugal}} [[Portugal]] || [[Setúbal]] || <ref>{{cite web|url=https://stats.ioinformatics.org/results/1998|title=IOI 1998 Results}}</ref>||
|-
| 11 || 1999 || October 9–16 || {{flagicon|Turkey}} [[Turkey]] || [[Antalya]]-[[Belek]] || <ref>{{cite web|url=https://stats.ioinformatics.org/results/1999|title=IOI 1999 Results}}</ref> ||
|-
| 12 || 2000 || September 23–30 || {{flagicon|CHN}} [[People's Republic of China|China]] || [[Beijing]] || <ref>{{cite web|url=https://stats.ioinformatics.org/results/2000|title=IOI 2000 Results}}</ref> ||
|-
| 13 || 2001 || July 14–21 || {{flagicon|FIN}} [[Finland]] || [[Tampere]] || <ref>{{cite web|url=https://stats.ioinformatics.org/results/2001|title=IOI 2001 Results}}</ref> ||
|-
| 14 || 2002 || August 18–25 || {{flagicon|KOR}} [[Republic of Korea|Korea Rep.]] || [[Yongin|Yong-In]] || <ref>{{cite web|url=https://stats.ioinformatics.org/results/2002|title=IOI 2002 Results}}</ref> ||
|-
| 15 || 2003 || August 16–23 || {{flagicon|USA}} [[United States]] || [[Kenosha, Wisconsin]] || <ref>{{cite web|url=https://stats.ioinformatics.org/results/2003|title=IOI 2003 Results}}</ref>||
|-
| 16 || 2004 || September 11–18 || {{flagicon|Greece}} [[Greece]] || [[Athens]] || <ref>{{cite web|url=https://stats.ioinformatics.org/results/2004|title=IOI 2004 Results}}</ref> ||
|-
| 17 || 2005 || August 18–25 || {{flagicon|POL}} [[Poland]] || [[Nowy Sącz]] || <ref>{{cite web|url=https://stats.ioinformatics.org/results/2005|title=IOI 2005 Results}}</ref> || <ref>{{cite web|url=https://www.oi.edu.pl/old/ioi/|title=IOI 2005 Website|website=ioi2005}}</ref>
|-
| 18 || 2006 || August 13–20 || {{flagicon|MEX}} [[Mexico]] || [[Mérida, Yucatán|Mérida]], [[Yucatán]] || <ref>{{cite web|url=https://stats.ioinformatics.org/results/2006|title=IOI 2006 Results}}</ref> ||
|-
| 19 || 2007 || August 15–22 || {{flagicon|Croatia}} [[Croatia]] || [[Zagreb]] || <ref>{{cite web|url=https://stats.ioinformatics.org/results/2007|title=IOI 2007 Results}}</ref> || <ref>{{cite web|url=https://ioi2007.hsin.hr/|title=IOI 2007 Website|website=ioi2007}}</ref>
|-
| 20 || 2008 || August 16–23 || {{flagicon|Egypt}} [[Egypt]] || [[Cairo]] || <ref>{{cite web|url=https://stats.ioinformatics.org/results/2008|title=IOI 2008 Results}}</ref> ||
|-
| 21 || 2009 || August 8–15 || {{flagicon|Bulgaria}} [[Bulgaria]] || [[Plovdiv]] || <ref>{{cite web|url=https://stats.ioinformatics.org/results/2009|title=IOI 2009 Results}}</ref> || <ref>{{cite web|url=http://www.ioi2009.org/|title=IOI 2009 Website|website=ioi2009.org}}</ref>
|-
| 22 || 2010 || August 14–21 || {{flagicon|CAN}} [[Canada]] || [[Waterloo, Ontario]] || <ref>{{cite web|url=https://stats.ioinformatics.org/results/2010|title=IOI 2010 Results}}</ref> || <ref>{{cite web|url=http://www.ioi2010.org/|title=IOI 2010 Website|website=ioi2010.org}}</ref>
|-
| 23 || 2011 || July 22–29 || {{flagicon|THA}} [[Thailand]] || [[Pattaya]] || <ref>{{cite web|url=https://stats.ioinformatics.org/results/2011|title=IOI 2011 Results}}</ref>|| <ref>{{cite web|url=http://www.ioi2011.or.th/|title=IOI 2011 Website|website=ioi2011|access-date=2010-07-28|archive-date=2010-09-04|archive-url=https://web.archive.org/web/20100904044842/http://www.ioi2011.or.th/|url-status=dead}}</ref>
|-
| 24 || 2012 || September 23–30 || {{flagicon|ITA}} [[Italy]] || [[Sirmione]] and [[Montichiari]] || <ref>{{cite web|url=https://stats.ioinformatics.org/results/2012|title=IOI 2012 Results}}</ref> || <ref>{{cite web|url=http://www.ioi2012.org/|title=IOI 2012 Website|website=ioi2012.org}}</ref>
|-
| 25 || 2013 || July 6–13 || {{flagicon|AUS}} [[Australia]] || [[Brisbane]] || <ref>{{cite web|url=https://stats.ioinformatics.org/results/2013|title=IOI 2013 Results}}</ref> || <ref>{{cite web|url=http://www.ioi2013.org/|title=IOI 2013 Website|website=ioi2013.org}}</ref>
|-
| 26 || 2014 || July 13–20 || {{flagicon|TWN}} [[Taiwan]] || [[Taipei]] || <ref>{{cite web|url=https://stats.ioinformatics.org/results/2014|title=IOI 2014 Results}}</ref> || <ref>{{cite web|url=http://www.ioi2014.org/|title=IOI 2014 Website|website=ioi2014.org}}</ref>
|-
| 27 || 2015 || July 26 – August 2 || {{flagicon|Kazakhstan}} [[Kazakhstan]] || [[Almaty]] || <ref>{{cite web|url=https://stats.ioinformatics.org/results/2015|title=IOI 2015 Results}}</ref> || <ref>{{cite web|url=http://www.ioi2015.kz/|title=IOI 2015 Website|website=ioi2017.kz}}</ref>
|-
| 28 || 2016 || August 12–19 || {{flagicon|RUS}} [[Russia]] || [[Kazan]] || <ref>{{cite web|url=https://stats.ioinformatics.org/results/2016|title=IOI 2016 Results}}</ref> || <ref>{{cite web|url=http://ioi2016.ru/|title=IOI 2016 Website|website=ioi2016.ru|access-date=2023-08-16|archive-date=2016-02-11|archive-url=https://web.archive.org/web/20160211185940/http://ioi2016.ru/|url-status=dead}}</ref>
|-
| 29 || 2017 || July 28 – August 4 || {{flagicon|IRN}} [[Iran]] || [[Tehran]] || <ref>{{cite web|url=https://stats.ioinformatics.org/results/2017|title=IOI 2017 Results}}</ref> || <ref>{{cite web|url=http://ioi2017.org/|title=IOI 2017 Website|website=ioi2017.org}}</ref>
|-
| 30 || 2018 || September 1–8
| {{flagicon|Japan}} [[Japan]]  || [[Tsukuba, Ibaraki|Tsukuba]] || <ref>{{cite web|url=https://stats.ioinformatics.org/results/2018|title=IOI 2018 Results}}</ref>|| <ref>{{cite web|url=https://ioi2018.jp/|title=IOI 2018 Website|website=ioi2018.jp}}</ref>
|-
| 31 || 2019 || August 4–11 || {{flagicon|Azerbaijan}} [[Azerbaijan]]  || [[Baku]] || <ref>{{cite web|url=https://stats.ioinformatics.org/results/2019|title=IOI 2019 Results}}</ref>|| <ref>{{cite web|url=https://ioi2019.az/|title=IOI 2019 Website|website=ioi2019.az|access-date=2023-08-16|archive-date=2022-04-01|archive-url=https://web.archive.org/web/20220401074332/https://ioi2019.az/|url-status=dead}}</ref>
|-
| 32 || 2020 || September 13–19{{ref|Alpha|a}} || {{flagicon|Singapore}} [[Singapore]] || ''online'' || <ref>{{cite web|url=https://stats.ioinformatics.org/results/2020|title=IOI 2020 Results}}</ref> || <ref>{{cite web|url=https://ioi2020.sg/|title=IOI 2020 Website|website=ioi2020.sg}}</ref>
|-
| 33 || 2021 || June 19–25 || {{flagicon|Singapore}} [[Singapore]] || ''online'' || <ref>{{cite web|url=https://stats.ioinformatics.org/results/2021|title=IOI 2021 Results}}</ref> || <ref>{{cite web|url=https://ioi2021.sg/|title=IOI 2021 Website|website=ioi2021.sg}}</ref>
|-
| 34 || 2022 || August 7–15 || {{flagicon|Indonesia}} [[Indonesia]] || [[Yogyakarta]] || <ref>{{cite web|url=https://stats.ioinformatics.org/results/2022|title=IOI 2022 Results}}</ref> || <ref>{{cite web|url=https://ioi2022.id/|title=IOI 2022 Website|website=ioi2022.id}}</ref>
|-
| 35 || 2023 || August 28 – September 4 || {{flagicon|Hungary}} [[Hungary]] || [[Szeged]] || <ref>{{cite web|url=https://stats.ioinformatics.org/results/2023|title=IOI 2023 Results}}</ref> || <ref>{{cite web|url=https://ioi2023.hu/|title=IOI 2023 Website|website=ioi2023.hu}}</ref>
|-
| 36 || 2024 || September 1–8 || {{flagicon|Egypt}} [[Egypt]] || [[Alexandria]] || <ref>{{cite web|url=https://stats.ioinformatics.org/results/2024|title=IOI 2024 Results}}</ref> || <ref>{{cite web|url=https://www.ioi2024.eg/|title=IOI 2024 Website|website=ioi2024.eg}}</ref>
|-
| 37 || 2025 || July 27 – August 3 || {{flagicon|Bolivia}} [[Bolivia]] || [[Sucre]] || || <ref>{{cite web|url=https://ioi2025.bo/|title=IOI 2025 Website|website=ioi2025.bo}}</ref>
|-
| 38 || 2026 || || {{flagicon|Uzbekistan}} [[Uzbekistan]] || || || <ref>{{cite web|url=https://ioi2026.uz/|title=IOI 2026 Website|website=ioi2026.uz}}</ref>
|-
| 39 || 2027 || || {{flagicon|Germany}} [[Germany]] || [[Potsdam]] || ||
|-
|}

==All-time medal table==

{{Medals table
 | caption        = As of 2024
 | gold_CHN = 102 | silver_CHN = 28 | bronze_CHN = 12
 | gold_RUS = 68 | silver_RUS = 40 | bronze_RUS = 12
 | gold_USA = 68 | silver_USA = 39 | bronze_USA = 16
 | gold_KOR = 49 | silver_KOR = 50 | bronze_KOR = 28
 | gold_POL = 44 | silver_POL = 52 | bronze_POL = 35
 | gold_JPN = 37 | silver_JPN = 30 | bronze_JPN = 10
 | gold_ROU = 34 | silver_ROU = 60 | bronze_ROU = 37
 | gold_IRN = 32 | silver_IRN = 67 | bronze_IRN = 24
 | gold_BGR = 27 | silver_BGR = 55 | bronze_BGR = 45
 | gold_SVK = 26 | silver_SVK = 45 | bronze_SVK = 36
}}

==Multiple IOI winners==

The following is a list of the top performers in the history of the IOI.<ref>{{cite web|url=http://stats.ioinformatics.org/halloffame/|title=Hall of Fame|website=stats.ioinformatics.org}}</ref> The <sup>P</sup> sign indicates a perfect score, a rare achievement in IOI history. The <sup>U</sup> sign indicates an unofficial participation, where a contestant participated in a host's second team. Also, first ('''I'''), second ('''II''') and third ('''III''') places among gold medalists are indicated where appropriate. 

{| class="wikitable" style="margin:auto" align="left"
|-
! Name || Team || colspan=7 | Years
|-
|[[Gennady Korotkevich]] || Belarus || '''G(II)''' 2012 || '''G<sup>P</sup>(I)''' 2011 || '''G(I)''' 2010 || '''G(I)''' 2009 || '''G''' 2008 || '''G''' 2007  || '''S''' 2006
|-
|Bruce Merry || South Africa || '''G''' 2001 || '''G''' 2000  || '''S''' 1999  || '''B''' 1998  || '''B''' 1997  || '''B''' 1996 ||
|-
|Rumen Hristov || Bulgaria || '''G''' 2012 || '''G''' 2011 || '''G(II)''' 2010  || '''S''' 2009  || '''S''' 2008 || ||
|-
|Hristo Venev || Bulgaria || '''G''' 2016 || '''G''' 2015 || '''G''' 2014 || '''G''' 2013 || '''S''' 2012 || ||
|-
|Encho Mishinev || Bulgaria || '''G''' 2017 || '''G''' 2014 || '''S''' 2016 || '''S''' 2015 || '''S''' 2013 || ||
|-
|Egor Lifar || Russia || '''G''' 2021 || '''G''' 2019 || '''S''' 2020 || '''S''' 2018 || '''S''' 2017 || ||
|-
|Harris Leung || Hong Kong || '''G''' 2021 || '''G(III)''' 2020  || '''S''' 2019  || '''B''' 2018 || '''B''' 2017 || ||
|-
|Zixiang Zhou || Canada || '''G''' 2022 || '''G''' 2021 || '''G''' 2020 || '''G(III)''' 2019 || '''S''' 2018 || ||
|-
|Wolfgang Thaller || Austria || '''G''' 1997 || '''G''' 1996 || '''S''' 1999 || '''S''' 1998 ||  ||  ||
|-
|Andrzej Gąsienica-Samek || Poland || '''G''' 1999 || '''G''' 1998 || '''G''' 1997 || '''S''' 1996 ||  ||  ||
|-
|Martin Pettai || Estonia || '''G''' 2002 || '''G''' 2001 || '''G''' 2000 || '''S''' 1999 ||  ||  ||
|-
|Alex Schwendner || United States || '''G''' 2005 || '''G''' 2003  || '''S''' 2004  || '''S''' 2002 ||  ||  ||
|-
|Filip Wolski || Poland || '''G(I)''' 2006 || '''G''' 2005 || '''G''' 2004 || '''G''' 2003 || || ||
|-
|Goran Žužić || Croatia || '''G''' 2008 || '''G''' 2007  || '''S''' 2009 || '''B''' 2006 ||  ||  ||
|-
|Vlad Alexandru Gavrilă || Romania || '''G''' 2013 || '''G''' 2012  || '''S''' 2011 || '''B''' 2010 ||  ||  ||
|-
|Eduard Batmendijn || Slovakia || '''G''' 2015 || '''G''' 2013 || '''G''' 2012  || '''S''' 2014 ||  ||  ||
|-
|Rareș Darius Buhai || Romania || '''G''' 2015 || '''G''' 2014 || '''G''' 2013  || '''G''' 2012 || ||  ||
|-
|Yuta Takaya || Japan || '''G(I)''' 2017 || '''G''' 2016 || '''G''' 2015 || '''G''' 2014 || || ||
|-
|Nikoloz Birkadze || Georgia || '''G''' 2020 || '''G''' 2019 || '''G''' 2018  || '''S''' 2017 ||  ||  ||
|-
|Dorijan Lendvaj || Croatia || '''G''' 2022 || '''G''' 2021  || '''S''' 2020 || '''B''' 2019 ||  ||  ||
|-
|Patrick Pavić || Croatia || '''G''' 2022 || '''G''' 2021 || '''G''' 2020  || '''S''' 2019 ||  ||  ||
|-
|Fredrik Huss || Sweden || '''G<sup>P</sup>(I)''' 1993 || '''G<sup>P</sup>(I)''' 1992 || '''S''' 1991 || || || ||
|-
|Martin Mareš || Czech Republic || '''G''' 1995 || '''G''' 1994  || '''G<sup>P</sup>(I)''' 1993 ||  ||  ||  ||
|-
|Vladimir Martianov || Russia || '''G''' 1999 || '''G<sup>P</sup>(I)''' 1998 || '''G(I)''' 1997 ||  ||  ||  ||
|-
|[[John Pardon]] || United States || '''G''' 2007 || '''G''' 2006  || '''G''' 2005 ||  ||  ||  ||
|-
|Marcin Andrychowicz || Poland || '''G''' 2008 || '''G''' 2007  || '''G''' 2006 ||  ||  ||  ||
|-
|Neal Wu || United States || '''G''' 2010 || '''G''' 2009  || '''G''' 2008 ||  ||  ||  ||
|-
|Shogo Murai || Japan || '''G''' 2012 || '''G''' 2011  || '''G''' 2010 ||  ||  ||  ||
|-
|[[Scott Wu]] || United States || '''G<sup>P</sup>(I)''' 2014 || '''G''' 2013 || '''G''' 2012 ||  ||  ||  ||
|-
|Jarosław Kwiecień || Poland || '''G''' 2016 || '''G''' 2015 || '''G''' 2014 ||  ||  ||  ||
|-
|Vladimir Romanov || Russia || '''G''' 2019 || '''G''' 2018 || '''G''' 2017 ||  ||  ||  ||
|-
|Masataka Yoneda || Japan || '''G''' 2020 || '''G''' 2019 || '''G<sup>U</sup>''' 2018  ||  ||  ||  ||
|-
|Daiki Kodama || Japan || '''G''' 2023 || '''G''' 2022 || '''G''' 2021  ||  ||  ||  ||
|-
|}
{{Clr}}

== Feeder competitions ==
Most participating countries use feeder competitions to select their team. A number of these are listed below:

{{columns-list|colwidth=30em|
* [[Australian Informatics Olympiad]]
* [[British Informatics Olympiad]]
* [[Canadian Computing Competition#Canadian Computing Olympiad (CCO)|Canadian Computing Olympiad]]
:* The participants of which are chosen from the [[Canadian Computing Competition]]
* [[Central European Olympiad in Informatics]]
* [[Indian Computing Olympiad]]
* [[National Olympiad in Informatics]]
* [[National Olympiad in Informatics, China]]
* {{ill|Olimpiada Națională de Informatică|ro}}<ref>http://olimpiada.info/Romanian National Informatics Olympiad {{Webarchive|url=https://web.archive.org/web/20190624190734/http://olimpiada.info/ |date=2019-06-24 }}</ref>
* {{ill|Nederlandse Informatica Olympiade|nl}}<ref>{{cite web| url = https://informaticaolympiade.nl| title = Informatica Olympiade}}</ref>
* {{ill|Olimpiada Mexicana de Informática|es}}
* [[South African Computer Olympiad]]
* [[Syrian Olympiad in Informatics]]
* United States of America Computing Olympiad<ref>{{Cite web |title=USACO |url=https://usaco.org/ |access-date=2025-02-16 |website=usaco.org}}</ref>
* [[Moroccan Olympiad in Informatics]]
* [[All Ireland Programming Olympiad]]
* [[Indonesian Olympiad in Informatics]]
* Egyptian Olympiad in Informatics
* [[National Olympiad in Informatics - Philippines]]<ref>{{cite web| url = https://noi.ph| title = Home — NOI.PH}}</ref>
* [[Bundeswettbewerb Informatik]] - Germany
* [[Vietnamese Olympiad in Informatics]]
}}
{{Further|National Olympiad in Informatics}}

== Notes ==
:1.{{note|Alpha|a}}IOI 2020 virtual closing ceremony was held on September 23, 2020.

== See also ==

* [[List of computer science awards]]
* [[International Science Olympiad]]
* [[International Collegiate Programming Contest]]
* [[Central European Olympiad in Informatics]]
* [[Competitive programming]]
* [[International Mathematical Olympiad]]

== References ==
{{reflist}}

== External links ==
{{Commons category}}
* [https://www.commonlounge.com/community/e4aac00a033a40ec96657906c6e1b43c International Olympiad in Informatics (IOI) community] {{Webarchive|url=https://web.archive.org/web/20220116192629/https://www.commonlounge.com/community/e4aac00a033a40ec96657906c6e1b43c |date=2022-01-16 }} (hosted on Commonlounge)
* [http://www.ioinformatics.org/ IOI International Committee Website]
* [http://stats.ioinformatics.org/ IOI Statistics]
* [http://olympiads.win.tue.nl/ioi/ IOI Secretariat Website]

{{International Science Olympiad}}

[[Category:Programming contests]]
[[Category:Computer science competitions]]
[[Category:Recurring events established in 1989]]
[[Category:International Science Olympiad]]