One problem a day

Daily coding challenge

A new problem every day at midnight UTC. Your clock starts when you open it; every wrong submission costs five minutes. Keep the streak.

0 day streak·0 problems solved· solved today

Challenges

Today's problem

closes in

--:--

0 solved · 0 sat

day streakbestsolved

Standings

3 / 4 / 5 points a solve by difficulty; ties go to the lower total penalty.

Tournaments · CodeKairo Battles

Compete for your college

1v1 knockouts and ICPC-style team contests hosted by colleges and clubs, on your CodeKairo account. Every accepted solve counts here too.

All tournaments

The calendar

November 2026

Daily coding challenge

A new problem every day for everyone, easy to hard by weekday. Time to Accepted plus penalties ranks the board; points build monthly and all-time standings.

What is the CodeKairo daily contest?

The daily contest is one coding problem a day, the same for everyone, released at midnight UTC (05:30 IST). Its difficulty follows the weekday — easy on Monday and Wednesday, medium on Tuesday, Thursday and Friday, hard on Saturday and Sunday — and a problem is not reused for a year. The day's board ranks entrants by the time from opening the problem to an accepted submission, plus five minutes for each wrong submission before it. Points of 3, 4 or 5 by difficulty build monthly and all-time standings and a contest streak, separate from the solving streak. When the day closes every solver is paid 20 XP, the fastest 15 more and the second fastest 10 more. The problem can be read without an account; entering needs a free one.

How it works

Open today's problem. The clock starts when you open it. The page shows the day's difficulty, the board so far and your contest streak.
Submit an accepted solution. Your time plus penalties places you on the day's board; a compile error costs nothing, every wrong submission five minutes. A problem you solved earlier must be submitted again on the day.
Build the ladder. Points accumulate on monthly and all-time standings, and the calendar marks every day solved, attempted or missed.

Who it is for

Anyone who wants a daily habit with a clock on it — one problem, one board, and a streak that notices a missed day.

Frequently asked questions

When does the problem change?

Once per UTC day — 05:30 in India. Difficulty follows the weekday: easy on Monday and Wednesday, medium on Tuesday, Thursday and Friday, hard on Saturday and Sunday. Everyone gets the same problem, and a problem is not reused for a year.

How is the day's board ranked?

By your time from opening the problem to the accepted submission, plus five minutes for every wrong submission before it — a compile error costs nothing. Ties go to whoever finished first.

What are the points?

Easy 3, medium 4, hard 5, on the contest's own ladder with monthly and all-time standings, separate from XP.

Does the daily contest pay XP?

Yes, when the day closes at midnight UTC (05:30 in India) and the next problem is set: 20 XP to everyone who solved it that day, plus 15 to the fastest on the day's board and 10 to the second fastest. Each solver gets a notification saying what they earned and why. It comes on top of the problem's normal first-solve XP.

Does a problem I solved earlier count?

No — you have to submit it again on the day. Consecutive days solved build a contest streak, separate from the solving streak, and the calendar shows every day as solved, attempted or missed.