Interior Design Certification Day (Interior Kentei no Hi)

What is Interior Design Certification Day?

January 10th is "Interior Design Certification Day" in Japan. It was established by the Japan Interior Vocational Skills Association to promote the proper knowledge and skills related to interior design. The date comes from a wordplay on "in" (1) and "te-ri-a" (10), echoing the word "interior." This day serves as a milestone for those aiming to become interior coordinators, as well as anyone wanting to improve their living space, to boost their motivation to learn and reassess their own skills.

Facts about the expertise behind designing living spaces

Interior design isn't just decoration—it has a scientific dimension that significantly affects human psychology and physiology.

• The effects of light and color: The brightness and color temperature of lighting, as well as the color of wallpaper, can affect brain activity, sleep quality, and even appetite. Interior design certification tests cover the theoretical knowledge needed to control these factors appropriately.
• Flow and layout: Even small changes in furniture placement can affect household efficiency and how family members communicate—a demonstration of the importance of ergonomically informed design.

Facts about environments that improve quality of life

A well-organized, comfortable interior directly contributes to reduced stress and increased happiness.

• Productivity and environment: With remote work now widespread, creating an interior environment conducive to focus has become essential for maximizing work performance.
• A sustainable perspective: In recent years, the interior design industry has placed growing importance on sustainable home-making—choosing materials that last and adopting furniture with a lower environmental impact.

Interesting facts about interior design

• The use of the "golden ratio": Arrangements that feel aesthetically pleasing often hide ratios like 5:3 or 3:2, which are applied to things like the number of cushions on a sofa or the size of artwork chosen for a wall.
• Air-purifying houseplants: Certain houseplants not only absorb harmful substances from the air and supply oxygen, but their visual presence also has a calming effect that can help stabilize blood pressure.
• The "focal point" rule: Creating just one focal point—the spot your eyes are drawn to first when entering a room—can dramatically improve the impression of the entire space.
• Expanding space with mirrors: Strategically placing mirrors on walls creates the illusion of depth, making small rooms appear larger and brighter—a fundamental technique in interior design.
• The design history of chairs: Many world-famous designer chairs were actually designed by architects, and a single chair can sometimes define the artistic character of an entire room.

The space around you shapes your ideal future

Interior Design Certification Day is a day to love the "environment" where you spend the most time, and to make it more beautiful and functional. Every color you choose and every piece of furniture you arrange becomes a stage that supports your mind and body and nurtures your energy for tomorrow. On January 10th, why not take a look around your room and think about what you truly need, and what kind of space would make you happiest? Organizing your living space is, in a sense, organizing your life. A comfortable space—a true "anchor for the mind"—can guide you toward freer, more creative days.

Ideas for enjoying Interior Design Certification Day

• Browse interior magazines or social media for ideas of your dream room, and write down small improvements you could make to your own space.
• Refresh your cushion covers or rearrange your artwork, taking time to draw new inspiration from visual changes.
• To mark January 10th, turn off one light and spend time with just candles or indirect lighting, feeling firsthand how lighting changes a space.
• Learn one piece of basic knowledge related to interior design certification—curtain materials, furniture dimensions, etc.—and look at the items around you with a more expert eye.

A beautifully arranged space brings vibrant harmony to your heart

January 10th is a day when your aesthetic sense sharpens and your everyday surroundings can be upgraded to a more refined stage. The small effort of arranging your environment will organize your thinking and act as a magnet that attracts new opportunities. The ability to create a space that feels comfortable and authentically yours is one of the finest skills for enriching life. May today be full of pleasant discoveries and a stepping stone toward a year that feels truly "at home."