SOF vs IOF: which olympiad suits your child?
Both run school olympiads on the school syllabus, with a certificate for every child. They differ in who can register, where your child sits the paper, the fee and the rounds.
- your child's school already runs SOF olympiads: registration is only through the school
- you want a second round for top scorers
- you want to know when results come: within 8 weeks, to the school and on SOF's results page
- you want to register your child yourself
- you want the option of sitting it from home
- you want the lower fee: from ₹150 against ₹170
- you want more subjects to choose from: 14 olympiads against 8
This year: IOF registration closed on 9 Oct 2026 for the October-December exams.
Side by side
| SOF | IOF | |
|---|---|---|
| Olympiads | 8, Classes 1 to 12 | 14, Classes 1 to 12 |
| Who registers | Through the school only; if your school doesn't run it, it can sign up free | You, or through a school link |
| Where | On paper, in your child's school | Online from home, any time 5 to 8 PM on exam day, a parent watching |
| Fee (India) | ₹170 per olympiad; the school may add up to ₹30 | ₹150 per olympiad |
| Paper | 35 questions (Classes 1 to 4) or 50 (Class 5 up), 60 minutes | 35 questions (Classes 1 to 5) or 50 (Class 6 up), 60 minutes |
| Rounds | Level 2 for maths, science and English (Classes 3 to 12) | Not published |
| Maths dates 2026-27 | IMO: 23 Oct (held), 26 Nov, 10 Dec 2026 | IFMO: 12 Dec 2026 (Classes 1 to 5); 13 Dec 2026 (Classes 6 to 12) |
| Last date to register | Through the school, usually 30 days before the exam date | Closed on 9 Oct 2026 for the October-December exams |
| Results | Within 8 weeks, to the school and on SOF's results page | Maths results 31 Jan 2027; others not published |
| Negative marking | Not published | Not published |
Full details: every SOF olympiad · every IOF olympiad · IMO · IFMO
Which is better, SOF or IOF?
Neither is better for every child. Start with which one your child can take (one is through the school and the other you can register for yourself), then pick the subjects your child enjoys.
Is IOF easier than SOF?
Neither organiser publishes a difficulty comparison. What can be compared is the paper. SOF: 35 questions (Classes 1 to 4) or 50 (Class 5 up), 60 minutes. IOF: 35 questions (Classes 1 to 5) or 50 (Class 6 up), 60 minutes.
Can my child take both?
Yes. They are separate organisers with separate papers, and their 2026-27 exam dates never fall on the same day.
Is SOF or IOF online or offline?
SOF: on paper, in your child's school. IOF: online from home, any time 5 to 8 PM on exam day, a parent watching.
Which olympiads can be taken from home?
Every olympiad date for 2026-27