転換をする

You will mostly see this used with specific nouns. The most famous partner for this phrase is kibun (mood). When you say kibun tenkan o suru, you are saying you need a change of pace to refresh your mind. You can also use it for houshin (policy) or senryaku (strategy). Grammatically, it is simple: [Noun] + o + tenkan suru. If you want to sound a bit more casual, you can drop the o and just say tenkan suru. It is like saying "I'm pivoting" versus "I am performing a pivot."

Use this when you are stuck in a rut. If you have been studying for five hours and your brain is mush, tell your friend, "I need a kibun tenkan!" It is also perfect for professional settings. If your startup was selling fax machines and now you are selling AI, that is a major houshin tenkan (policy shift). You might also hear it in news reports about energy, like "converting" from coal to solar power. It feels decisive and forward-moving.

Do not use this for small, physical changes. If you are changing your clothes, use kigaeru. If you are changing your mind about which ramen to order, use kaeru. Tenkan is too heavy for those situations. Also, avoid using it for file conversions on a computer. For turning a Word doc into a PDF, the word is henkan, not tenkan. Using tenkan there would sound like your computer is having a mid-life crisis and changing its philosophy!

In Japan, the concept of kirikae (switching) is huge. Japanese culture values the ability to leave work stress at the office and be present at home. Tenkan o suru is the action that makes this possible. It is a mental discipline. There is even a cultural appreciation for "diversions"—small activities like gardening or a quick walk—specifically to facilitate this shift. It is seen as a sign of maturity to be able to "convert" your mood effectively.

The most common variation is kibun tenkan (change of pace/mood). You will also hear houshin tenkan (policy change) in the news. In a more technical sense, denkan (energy conversion) uses the same kanji roots. Sometimes people use the verb tenkan suru on its own to mean "to pivot" in a general sense. If you want to sound extra formal, you can use tenkan o hakaru, which means "to aim for a conversion."