Happiness Day (Kōfuku no Hi)

What Is Happiness Day?

Every year on May 29, Japan observes "Kōfuku no Hi" (Happiness Day). The date comes from the wordplay "ko (5) u fu (2) ku (9)," which together sound like "kōfuku," the Japanese word for "happiness." It was established by Daimaru Matsuzakaya Department Stores Co., Ltd. with the aim of giving people, amid the rush of daily life, a chance to rediscover the small joys close at hand and reflect on their own happiness as well as that of the people around them. Coming at the end of May, when the fatigue of the new fiscal year tends to build up, it's a day that suggests the importance of taking time to fill your heart.

Historical Facts About Humanity's Pursuit of Happiness

"What is happiness?" is a question that philosophy, religion, and modern science have all grappled with since ancient times.

• "The greatest happiness for the greatest number": In the 18th century, the British philosopher Jeremy Bentham proposed utilitarianism, which judges the value of a society by how many people in it are happy. This idea became one of the scientific foundations of today's concept of well-being and modern social policy.
• The launch of the World Happiness Report: Since 2012, the United Nations has published the "World Happiness Report." Rather than relying only on GDP, it scores each country's happiness using multiple factors — healthy life expectancy, social support, freedom, and more — and this kind of scientific, multi-dimensional analysis has become an international standard.

The Science of the Brain Chemicals Behind "Happiness"

The feeling we call "happiness" is, scientifically speaking, controlled by specific chemicals (neurotransmitters) released in the brain.

• Serotonin (mental and physical stability): Released through sunlight exposure and rhythmic exercise, serotonin governs a sense of "calm happiness" — easing anxiety and stabilizing the mind. A shortage of it has been linked, in psychiatric research, to feelings of low mood.
• Oxytocin (connection and love): Released through interaction with other people or pets, oxytocin is known as the "bonding hormone." It has been scientifically shown to lower blood pressure, reduce stress, and increase trust in others.

Interesting Facts About Happiness

• Can you "save up" happiness? Research in positive psychology shows that the habit of writing down three things you're grateful for each day ("three good things") strengthens the brain's reward system and has been scientifically shown to significantly improve long-term happiness.
• The link between income and happiness: Studies suggest that happiness rises along with income up to a certain point (in Japan, often cited as around 8 million yen per year), but beyond that point, the gains in happiness level off. This is scientific evidence that material wealth and emotional satisfaction aren't always directly proportional.
• The happiness of sharing: Research in neuroeconomics has shown that spending money on others — through gifts or donations — activates the brain's happiness-related regions more strongly than spending it on yourself.
• The high happiness levels of Nordic countries: Countries like Finland and Denmark consistently rank near the top of world happiness rankings. This is thought to be due not only to strong social welfare systems but also to cultural attitudes — such as "hygge" — that value small everyday pleasures, contributing to people's sense of psychological safety.
• Happiness is contagious: Social network analysis has found that when an individual's happiness rises, it can spread to friends of friends — even up to three degrees of separation. Happiness is both a personal emotion and a scientifically documented social phenomenon that spreads through networks.

Ideas for Spending Happiness Day

• To mark May 29 (Happiness Day), write down just three good things that happened today. This trains your brain to focus on positive information, helping to scientifically reset a mind worn down by new-fiscal-year stress.
• Send a message of thanks to someone important to you. Expressing gratitude releases oxytocin in the brains of both the giver and the receiver, making it one of the most efficient ways to boost happiness for both people at once.
• Build a morning routine focused on serotonin — spend five minutes in the May sunlight, take some deep breaths. These small physical actions help set up your brain to start the day in a state that's more receptive to happiness.
• Try putting your own "definition of happiness" into words. Rather than following trends or others' opinions, think about the moments when you feel truly fulfilled. Analyzing yourself based on real evidence can give you a solid compass for the second half of the fiscal year.

When You Cherish the Quiet, Nameless Joys Scattered Through Everyday Life, Your Heart Fills with a Gentle Glow That Leads to a Truly Rich Future

May 29 is a day to look at the world through slightly kinder eyes. Happiness isn't some grand goal far off in the future — it lives in the breath you're taking right now, the aroma of a cup of coffee, the smile of someone dear to you. As the new fiscal year pushes you toward ambitious goals, has your heart started to feel a little dry? Today, take a break from being hard on yourself, and simply say "thank you" to the self that's been working so hard. When you can acknowledge your own happiness, that warmth spreads outward, gradually making the world a little brighter. Plant a seed of small happiness in your heart today — it will eventually bear fruit beyond what you can imagine.