HKOI Online Judge ( is originally the training platform for the HKOI Training Team. Students can submit programs to improve their programming and problem solving skills. To further promote computational thinking and STEM education, the Online Judge is now open to secondary schools in Hong Kong.

(1) Suitable for students preparing for HKOI and/or studying HKDSE ICT.
(2) Used by more than 1700 students from 44 subscriber schools in 2020/21.
(3) 800+ tasks and counting. 50+ fundamental tasks.
(4) Bilingual interface. Supports a variety of programming languages: C, C++, Pascal, Java, Python, Blockly
(5) Online coding environment with mobile and touch screen support.
(6) Teachers may monitor students’ progress using their administrator accounts.

Enter HKOI Online Judge

Introduction slides. (Google Slides / PDF Version)


A subscription fee is required for using the HKOI Online Judge. The fees help us offset the increasing costs of operating the Online Judge, running the competitions and other activities.

Fees for School Year 2021/22 (accounts valid until 2022-09-30)

(Unlimited time)
Individual Student License School License
(Basic version)
School License
(Full version)
License fee Free HK$150 per student HK$2500 HK$4500
Student licenses N/A 1 per student
(cannot be reassigned)
Unlimited Unlimited
Full-time teacher licenses Up to 3 Up to 3 Up to 6 Up to 6
Instructor licenses N/A N/A N/A Up to 2
(can be reassigned)
Features All existing features that were available in 2020/21 + Task hosting
(available in Oct 2021)
school membership
N/A Complimentary*

For detailed license terms, please refer to the HKOI Online Judge Terms of Use.

Task hosting is for School Admins to upload tasks designed by them. The tasks will only be visible to the users in the same school. More details will be available in due course.

* Not valid for existing members and no refund of membership fee will be offered.

Sign Up @ Join HKOI

Please refer to the following presentation for step-by-step instructions. (Google Slides / PDF Version)