KOSPI Close Challenge: official rules
Last updated October 16, 2026
Who can play
You must be 18 or older, have a JONBUR account with a confirmed email address, and play with one account only. Void where prohibited by law.
Free to play
The challenge is free. Guesses cost paper money from your Bonus wallet, which you can only earn on JONBUR (sign-up bonus, daily check-ins, the daily quiz, missions, invites and prizes). It can never be bought.
Paper money
Paper money is play money for practising. It has no cash value and can't be sold, exchanged, transferred to other people or turned into anything real. You can move it from your Bonus wallet into your own paper portfolios, never back.
Rounds
There is one round for each Korean trading day. You guess the official KOSPI closing level for that day, to two decimals. Entries close at 00:00 Korea time (KST) on that day. Up to 10 guesses per person per round; guesses can't be changed or withdrawn.
How winners are chosen
After the official close is published, each player's closest guess counts. The guess (or guesses) closest to the close wins the round's prize. A guess equal to the close to the cent wins the grand prize and one month of Premium.
Ties
Equally close guesses from different players share the prize equally, rounded down to the nearest won. The same applies to the grand prize.
Fair play
One account per person. We check for several accounts on one device or network, and we may disqualify entries, take back prizes or close accounts that break these rules or the community guidelines.
Changes and cancellations
We may cancel a round (for example if no official close is published, or something goes wrong); its guesses are refunded to your Bonus wallet. We may change prizes, costs or these rules for future rounds.
Not advice
The challenge is a game. Nothing on it is investment advice, a prediction or a recommendation.