Kagami biraki is a traditional Japanese ceremony to break the ornamental mochi and eat it for good health and fortune for the New Year.
To conclude the Japanese New Year celebrations, kagami biraki (鏡開き), literally meaning ‘opening the mirror’ or breaking of the mochi, is typically held on January 11th.
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What is Kagami Biraki?
Kagami biraki is a ceremony that marks significant events or transitions to new stages in life. It originated from an act performed by the fourth Tokugawa shogun 300 years ago when he broke a sake barrel on the eve of war upon achieving victory. This act gave rise to a new tradition, signifying the beginning of something new.
The term ‘kagami’ translates to ‘mirror,’ and ‘biraki’ means ‘opening’ or ‘to break.’ Why ‘mirror’? The name ‘kagami’ is derived from its resemblance to an old-fashioned round copper mirror, which also held religious significance according to Japanese mythology.
In modern-day Japan, kagami biraki is performed at weddings, sporting events, housewarmings, the opening days of new companies, and other celebratory occasions.
Kagami Biraki Celebration During the New Year
The most common kagami biraki celebration is held right after the start of the New Year and involves breaking the kagami mochi (鏡餅), a pair of decorated rice cakes offered to the deity of the New Year.
Originally, kagami biraki was celebrated on January 20th. However, with the death of the third Shogun, Iemitsu, in the Tokugawa shogunate on January 20, 1651, it was changed to the 11th, as odd numbers are considered auspicious in Japan.
There are slight regional variations in the date. In the western part of Japan, it’s celebrated on January 15th, while in Kyoto and the surrounding area, the tradition takes place on the 4th.
The ceremony involves removing the round-shaped mochi from the family altar and breaking them into smaller pieces before cooking them in dessert or soup to enjoy. Eating the mochi symbolizes a prayer for health and good fortune in the New Year.
Ancient people believed that food offered to God would possess special powers, and by consuming it with the blessings from God, they wished for good health.
Do and Don’ts of the Ceremony
To break open the ornamental mochi, one should never cut it with a knife. The action reminds the Japanese people of seppuku (切腹), ritual disembowelment from ancient times, and it is considered a sign of bad luck. For that reason, the customary way to break the mochi is with a wooden hammer or with one’s hands.
The words ‘kiru‘ (to cut) and ‘waru‘ (to break) carry connotations of bad fortune and mishap; therefore, ‘hiraku’ (open) — the original form of ‘Biraki’ — is used in the sense of the opening of new opportunities.
Different Styles of Kagami Mochi Decoration
Traditionally, mochi was made fresh at home, including kagami mochi, which consisted of two discs—one slightly larger than the other.
The mochi cakes are stacked on a decorated stand, adorned with an orange and a fan, and placed on the kamidana (a Shinto altar) or family altar. To maximize luck, some families even place small kagami mochi in each room of the house.
These days, most families buy plastic kagami mochi from grocery stores. Inside the kagami mochi mold, there are individually packaged small mochi pieces (we call this rectangular mochi kiri mochi) for convenience and better preservation.
Where to Buy Kagami Mochi Decoration
As I mentioned earlier, kagami mochi decorations can be purchased at Japanese grocery stores in December. Since this is very specific to Japanese celebrations, it’s unlikely that general Asian grocery stores carry it. You may want to check Amazon to see if they offer it in December.
To reduce plastic usage, I purchased this hinoki kagami mochi decoration for this New Year.
The best part is that you can store the decoration in one box.
I like how simple and minimal this wooden kagami mochi looks. The store I purchased it from currently sold out of the product. If I find a new source, I’ll share the link in this post.
How Can We Use Kagami Mochi
After the ceremony, we will use the broken mochi pieces to make Zenzai (Red Bean Soup with Mochi), Chikara Udon (udon noodle soup with mochi), or include it in Ozoni (New Year Soup).
Red Bean Soup with Mochi (Zenzai / Oshiruko)
Kansai-style Ozoni (New Year Mochi Soup)
Kanto-style Ozoni (New Year Mochi Soup)
If you are tired of eating soups, try making rice cracker snacks!
Other “Kagami Biraki” Celebrations
1. Kagami Biraki in Dojo and Other Sporting Events
The Kagami Biraki ceremony is also a significant event in many dojos (traditional martial art schools such as judo, karate, jujutsu, kendo, aikido, etc.) to kick off the dojo’s new year. The ceremony is usually held on the second Saturday or Sunday of January, so all students will be able to attend their first practice of the year. It marks a tradition of renewal, spirit, and devotion.
With the same vision in mind, many other sports communities in Japan also adopt the ceremony to mark a new season for their teams and to welcome new members.
2. The Other Kagami Biraki: Sake Barrel Ceremony
Another popular kagami biraki ceremony involves breaking the lid of sake barrel using a wooden mallet, and the sake is served and partaken by everyone present at the event. The act of ‘breaking open the lid’ of the sake barrel is similar to the act of breaking the mochi, and it represents an opening to harmony and good fortune.
In the picture above, the lid of the sake is opened using a wooden mallet called kizuchi (木槌) and a wooden ladle hishaku (柄杓), is used to fill the square masu (升) cups with sake from the barrel.
At sake breweries, the lid of the sake barrel is called ‘kagami.’ This custom of opening the barrel is also referred to as kagami wari (鏡割り) ‘mirror breaking’ or kagami nuki (鏡抜き) ‘mirror pulling,’ but kagami biraki is commonly used for happy occasions.
You will find this version of kagami biraki more common at weddings, business openings, project completion ceremonies, graduation parties, or other events likely to involve sake drinking.
More on Japanese Culture & Traditions
- How Do Japanese Celebrate New Year
- Setsubun: The Japanese Bean Throwing Festival
- Hinamatsuri: Japanese Girls’ Day Celebration & Recipes
- Children’s Day (Boys’ Day) & 10 Recipes to Celebrate
- Japanese Winter Solstice Traditions (Toji)
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Editor’s Note: This post was originally published on January 10, 2017. It’s been republished on January 4, 2024.
One thing I’ve never understood about the kagami mochi, is if it’s the little hard bricks inside the plastic decorations, how are people supposed to break it apart with their hands? They’re so small and it must be like trying to break apart a piece of wood. I get the decorations each year with the zodiac characters on them (usually–this year I got Baymax) but I have actually never taken the mochi out of them and in fact never knew they had anything in them for years, since all the packaging was in Japanese, lol. Thank goodness for all these educational blogs such as yours!
Hello, Jeanine. We’re delighted Nami’s post was helpful.
We hope you enjoy cooking the small mochi inside the plastic Kagamimochi from now on. 🤗 When you open the plastic Kagami mochi, we believe it is part of Kagami Biraki; thus, there is no need to break it apart. We hope this helps!
My kid got a mochi machine for the holidays and we were thinking of making kagami mochi with it, but how long can we leave freshly made mochi out? Is only the plastic version safe to eat after two weeks of display? Thanks 🙂
Hi, Sam! Wow! That is an excellent gift!
If there is no mold growth, homemade Kagami mochi can be stored for an extended period of time. It will harden, but it is still suitable for Ozoni, Oshiruko, and other purposes. To maintain it fresh until Kagamibiraki day, spray the high alcohol, such as Shochu, every day.
We hope you enjoy the homemade mochi!
ナミさん、
あけましておめでとうございます。
日本にお住まいの方に祈っています。
鏡開の記事ありがとうございます。
勉強になりました。
Hello, Kim. Thank you for reading Nami’s post and praying for Japan.
明けましておめでとうございます。日本へのお祈りありがとうございます！💞
I love the traditions of other cultures. So much more interesting than ours. These hinoki kagami mochi are amazing! Thanks for sharing and wishing you and yours a wonderful 2022!
Hi mjskitchen! Happy New Year!🎉 Thank you very much for reading Nami’s post!
Hi Nami, This article is wonderful! I was curious about the hinoki kagami mochi you have. Is it hollow on the insides so you could “refill” the mochi for the current new year or is it solid wood?
Thank you!
Hi Mai! Thank you very much for reading Nami’s post and for your kind feedback!
The inside of Hinoki Kagami Mochi is hollow, but it does not have a lot of space. (Please see the inside-the-box photo. (under Hinoki Kagami mochi photo in this post) The top mochi part will fit inside the bottom mochi part.)
We hope this helps!
Thank you for writing an article about kagami mochi with the correct information. Even Wikipedia has kagami mochi incorrect and incomplete. I had a small, store bought kagami mochi this year (2021). Once out of the vacuum pack, I microwaved it for a bit, and it softened the mochi enough where I could tear it apart by hand. I made oshiruko with half of it, and the other half I ate in various other ways.
Hi Albert, Thank you very much for reading this post and for your kind feedback! We are glad to hear how you enjoyed Kagami mochi in various ways.
Happy New Year!
Never too late to learn .
Thanks for sharing the story/history about Kagami Biraki.
Hi Hideko-san! Thank you for reading! 🙂
I have so enjoyed your site especially the recipes. I have always enjoyed Japanese cuisine and am now living in an area where there are few Japanese restaurants and have found your site very helpful with cooking things up myself.
Thank you so much, looking forward to more fun recipes. Have a super year.
Hi Robert! Thank you so much for your kind feedback! I look forward to sharing more recipes this year! Happy New Year!
Oshogatsu omedetoo!
Akemashite Omedeto Georgia!
Thank you for this very interesting post. I had seen these for sale in Tokyo when I lived there but never really understood how they were used.
Hi Ann! I’m happy to hear you liked this post. Thank you for your kind comment, Ann! 🙂
I love reading your blog and learning so much about Japanese traditions which are close to my heart ( I lived in Japan for a few years). I have passed your information onto a few friends who also livied in Japan for a while, and they too are enjoying your recipes and information. It makes us all natsukashi~
Happy New Year!
Happy New Year Kristin! Thank you so much for reading my blog posts. Thank you for passing my blog post to your friends! I’m so happy you are still enjoying Japanese food! xoxo
Which religion comes into play? Shinto or Buddhist?
Hi Linda! It’s actually both when it comes to New Year’s! 🙂
That was so interesting! Thank you, Nami!
Thank you for reading, Anne! xo
I loved gainng more of an insight into Japanese traditions.. thank you! May all the world’s peoples break and eat a symbolic mochi this year
Hi Sally! Thank you for reading my post about Japanese traditions. 🙂
Nami, Thank You so much for sharing about the Kagami Biraki ceremonies. I am Sansei, third generation Japanese American, but never knew what happened to Kagami Mochi after the New Year’s. My family never ate it, so I never knew what my mother did with it. Just the other day my friends told me that they used to give the kagami Mochi to a friend’s husband by Jan 19, and he would burn it. But they didn’t know WHY he did that! Lol. My husband and I go to Mochi pounding every year with some friends, but we don’t pound unless our adult children are home. I either serve the Mochi in ozoni, or as a dessert….softened and covered with kinako and sugar!
Hey, as far as I’m aware in Japan the New Years decorations such as the kadomatsu and shime wreaths need to be burned. It may be that your family friend thought the Kagami mochi also needed to be burned rather than eaten! 🙂 Your freshly pounded mochi must taste incredible!
Ok ok, I think you’re right, it was just the kadomatsu. And yes, our freshly pounded Mochi IS pretty incredible! The best thing about it is seeing everyone for this once a year event….we’ve watched the children of the families grow up! I have pictures of my daughter at preschool age at Mochi pounding, and she is now 27!!!
Hi Aunty Mara! Since I published the post, I’ve received some emails from Japanese descendants like you! Thank you for making me feel good about posting this topic!
I have a Japanese American friend and his family gather for mochi pounding during New Year’s too! I thought it’s really cool since less people pound mochi as a “family event” in Japan and no one has kine and usu anymore. I hope the tradition will keep going!
Thank you Moopflop for mentioning about the burning!