How to play Koi-Koi in one breath: you and an opponent take turns matching flower cards from your hand to cards on the table, you collect what you match, and the first person to build a scoring combination (a yaku) can either cash out right away or shout "koi-koi!" and gamble for a bigger score. That's the whole game. Below are the rules for beginners, the full yaku table, and a few tips that stop you from making the classic first-timer mistakes.
In this article
The goal and the deck
Koi-Koi (pronounced "koy-koy", Japanese for "come on!") is the most popular game played with hanafuda, the 48-card Japanese flower deck. The deck has twelve months, four cards per month. Every card belongs to one of four types, and that type is what scores points:
- 5 Brights (Hikari) - the rarest and most valuable.
- 9 Animals (Tane) - boar, deer, butterfly, geese, and so on.
- 10 Ribbons (Tan) - red poetry ribbons, blue ribbons and plain red ones.
- 24 Plains (Kasu) - the "chaff". Worth the least, but there are lots of them.
A normal game is 12 rounds (one per month), though 3 or 6 rounds is a common short game. Whoever has the most points at the end wins. If you want the full month-by-month card list first, our hanafuda cards meaning guide walks through all 48.
Setup and the turn
Deal 8 cards to each player and 8 face-up to the table. The rest form a face-down draw pile. Then, on your turn:
- Play from your hand. Put down a card that matches a table card by month (same flower). Take both cards into your capture pile. No match? Discard a card to the table instead.
- Draw from the pile. Flip the top card. Same rule: if it matches a table card, capture both; if not, it stays on the table.
- Check for a yaku. If your captures just made a scoring combination, you get to make the big decision (below). If not, it's your opponent's turn.
Match rules worth knowing. If two table cards share your card's month, you take one of them (your choice). If three are already on the table, one play of the fourth takes all four. You can only capture by matching month, never by type.
The koi-koi decision
This is what makes the game. The moment you complete a yaku you have two options:
- Stop (Shobu). End the round and score your yaku. Safe.
- Call "koi-koi!" Keep playing, hoping to build a bigger combination. If you form another yaku (or extend one), you can stop again with the higher total. But if your opponent builds a yaku first, they win the round, and usually the points you were sitting on are lost.
A good rule of thumb for beginners: call koi-koi only when you are one card from a much bigger hand and your opponent has captured almost nothing of value. If your yaku is small and the Brights are already gone, take the points.
The yaku table
These are the standard yaku and the point values used by the Classic Koi-Koi mode in Moonlit Hanafuda. Different clubs and apps tweak a few values (for example Three Brights is 5 in some rulesets), so agree on a table before you play real opponents. Filter by type:
| Yaku | What you need | Points |
|---|---|---|
| Five Brights (Goko) | All 5 Bright cards | 10 |
| Four Brights (Shiko) | Any 4 Brights except the Rain Man | 8 |
| Rainy Four Brights (Ame-Shiko) | 4 Brights including the Rain Man | 7 |
| Three Brights (Sanko) | Any 3 Brights except the Rain Man | 6 |
| Boar-Deer-Butterfly (Inoshikacho) | The Boar, the Deer and the Butterfly | 5 |
| Red Poetry Ribbons (Akatan) | The 3 red poem-ribbons: Pine, Plum, Cherry | 5 |
| Blue Ribbons (Aotan) | The 3 blue ribbons: Peony, Chrysanthemum, Maple | 5 |
| Moon Viewing (Tsukimi-zake) | The Full Moon + the Sake Cup | 5 |
| Flower Viewing (Hanami-zake) | The Curtain (Cherry) + the Sake Cup | 5 |
| Animals (Tane) | Any 5 Animal cards (+1 per extra) | 1 |
| Ribbons (Tan) | Any 5 Ribbon cards (+1 per extra) | 1 |
| Plains (Kasu) | Any 10 Plain cards (+1 per extra) | 1 |
Only the best Bright yaku counts: you don't add Three Brights on top of Four Brights. Everything else stacks, so Animals plus Ribbons plus a Sake yaku can add up fast.
Beginner tips that actually help
- Go for the Brights early. Capturing the Moon, Curtain or Phoenix denies your opponent too. A single Bright card is worth more than any plain.
- Watch what you give away. Discarding a Plain next to a Bright of the same month lets your opponent grab the Bright. Only lead with a month when the other cards of it are safe.
- Don't ignore the Sake Cup. It counts toward both Moon Viewing and Flower Viewing, and it's also an Animal.
- Count the Plains. Ten Plains is only 1 point, but it's the easy fallback when the pretty cards are gone.
- Be boring when you're ahead. The way to lose at koi-koi is to push your luck. Winning small rounds beats losing big ones.
Practice it for free
Reading rules is a slow way to learn a card game. Moonlit Hanafuda has a Classic Koi-Koi mode against an Easy, Normal or Hard computer opponent, with the real yaku and the real koi-koi call, plus a built-in yaku book so you can check a combination without leaving the game. It also has a roguelike mode where the same combos are scored as chips times a multiplier. It runs in your browser on phone or PC, no download. The demo below is the roguelike mode's attract screen, where a bot plays a run so you can see the cards and combos in motion.
Try a round of Classic Koi-Koi
Pick Easy, learn the flow in two or three rounds, then step up when you are ready. It is free to try in your browser.
FAQ
How do you play koi-koi?
Each player gets 8 cards and 8 are laid on the table. On your turn you match a card from your hand to a table card of the same month and capture both, then flip a card from the draw pile and do the same. When your captures form a yaku (a scoring combination), you either stop and score it, or call koi-koi and keep playing for more.
What does koi-koi mean?
It is Japanese for roughly "come on" or "come here". In the game it is what you say when you complete a yaku but choose to keep playing instead of scoring right away.
What is a yaku in koi-koi?
A yaku is a scoring combination of captured cards, such as Three Brights, the Red Poetry Ribbons or Moon Viewing. You need at least one yaku to win a round.
How many points do you need to win koi-koi?
There is no fixed target. You win a round by completing a yaku and stopping before your opponent does. A game usually lasts 12 rounds (one per month), and whoever has the most total points at the end wins. Shorter 3 or 6 round games are common too.
What happens if you say koi-koi and then lose?
If you call koi-koi and your opponent completes a yaku before you improve yours, they win the round and you do not score the yaku you had. That risk is what makes the call interesting.
Is koi-koi the same as hanafuda?
Not exactly. Hanafuda is the name of the 48-card deck. Koi-Koi is one of the most popular games you can play with it. Others include Hachi-Hachi and Hana-Awase.
Can I play koi-koi online for free?
Yes. Moonlit Hanafuda has a free Classic Koi-Koi mode you can play against a computer opponent right in your browser, with no download.