Overview
The Indian National Olympiad in Informatics (INOI) is the second, national-level round of the Indian Computing Olympiad (ICO), the pathway that selects India's team for the International Olympiad in Informatics (IOI). The programme is organised by the Indian Association for Research in Computing Science (IARCS), with the current cycle run in cooperation with CodeChef and technical support from Amrita University and Justuju.
Who can take part
Any student enrolled in school up to Class 12 during the relevant academic year is eligible for the Indian Computing Olympiad; there is no minimum age requirement, but students must remain enrolled in school. To reach INOI, a student must first qualify through one of the two first-round exams: the Zonal Informatics Olympiad (ZIO) or the Zonal Computing Olympiad (ZCO).
Stages and pathway
| Stage | Round | What happens |
|---|---|---|
| 1a | Zonal Informatics Olympiad (ZIO) | Written exam testing computational thinking; no programming required |
| 1b | Zonal Computing Olympiad (ZCO) | Programming exam in C++, Java or Python |
| 2 | INOI | National round, programming only, in C++ |
| 3 | IOI Training Camp (IOITC) | About 30 INOI qualifiers attend a training-and-selection camp |
| 4 | International Olympiad in Informatics (IOI) | India's selected team competes internationally |
Students can attempt ZIO, ZCO, or both; either route can lead to an INOI invitation.
Exam pattern
| Round | Format | Language(s) allowed |
|---|---|---|
| ZIO | Written exam, no coding | Not applicable |
| ZCO | Programming exam | C++, Java, Python |
| INOI | Programming exam only | C++ only |
Syllabus
ZIO and ZCO are based on IARCS's own online study material covering basic programming and algorithmic thinking. INOI and the IOI Training Camp follow the syllabus standards used internationally for the IOI, which centres on algorithms, data structures and competitive programming.
Results and awards
For the 2025-26 cycle: ZIO-2026, held on 15 November 2025, had 612 students write the exam, of whom 152 qualified for INOI-2026. ZCO-2026, held on 8 February 2026, had 454 students write the exam, of whom 125 qualified. At INOI-2026 itself, 61 students were awarded medals (10 gold, 20 silver, 31 bronze); 36 qualified for the IOI Training Camp (IOITC-2026), and 12 were shortlisted for the separate selection process for the European Girls' Olympiad in Informatics (EGOI-2026). IOITC-2026 ran from 1 to 12 June 2026 in Chennai.
Important dates
For the 2025-26 cycle: ZIO-2026 was held Saturday, 15 November 2025; ZCO-2026 was held Sunday, 8 February 2026; INOI-2026 was held Saturday, 14 February 2026. Registration for the next cycle, ICO-2027, opens in October 2026.
How to register
Registration for ZIO and ZCO (the entry points into the pathway) opens on the IARCS website; INOI itself has no separate registration, as invitations go automatically to ZIO/ZCO qualifiers.
Preparation tips
Since INOI is programming-only in C++, students who reach it from ZIO (a non-coding round) need to build hands-on coding practice before INOI, not just algorithmic reasoning. Working through IARCS's own ZIO/ZCO study material first, then past INOI problem sets, follows the structure the organisers themselves point to.
Do I need to know how to code to attempt the first round?
Not necessarily. ZIO tests computational thinking without requiring code, while ZCO is a programming exam. Either can qualify a student for INOI, but INOI itself requires programming in C++.
Which programming languages are allowed at each stage?
ZCO allows C++, Java or Python. INOI allows only C++.
Is there an age limit for the Indian Computing Olympiad?
There is no minimum age requirement; a student needs to be enrolled in school up to Class 12 during the year of participation.
What happens after INOI?
Top INOI performers are invited to the IOI Training Camp (IOITC), a selection-and-training camp that picks the team representing India at the International Olympiad in Informatics.