Counting Frequency and Occurrences with ～回 (kai)

Using 回 is like building a Lego tower. You take a number and snap the counter 回 onto the end. In English, we have special words like "once" or "twice." Japanese is much more consistent. It mostly just uses "Number + 回." However, Japanese loves to keep you on your toes with pronunciation. Some numbers blend into the counter, creating a small pause or a double consonant. You will notice this especially with 1, 6, 8, and 10. It is like the words are giving each other a high-five and merging. Once you master these small shifts, you will sound like a pro. You can place this phrase directly before a verb or use it with particles like に (ni) to show frequency over time.

1. 1To count occurrences, follow these steps:
2. 2Pick the number of times you did something.
3. 3Add the counter 回 (kai) after the number.
4. 4Watch out for the "Big Four" pronunciation changes:
5. 51 time: 一回 (ikkai) - Not ichikai!
6. 66 times: 六回 (rokkai) - Not rokukai!
7. 78 times: 八回 (hakkai) - Not hachikai!
8. 810 times: 十回 (jukkai or jikkai) - Both are okay, but jukkai is more common.
9. 9For all other numbers, just say the number + kai. For example, 三回 (sankai) or 五回 (gokai).
10. 10To ask "how many times," use 何回 (nankai).

Use 回 whenever you are counting a repeated action.

• Daily Habits: "I brush my teeth three times a day." (一日に三回).
• Travel Memories: "I have been to Kyoto five times." (京都に五回行きました).
• Medical Advice: "Take this medicine two times a day." (一日に二回).
• Entertainment: "I watched that trailer ten times!" (その予告を十回見ました).
• Sports and Fitness: "Do fifteen reps of this exercise." (十五回やってください).

It is perfect for any scenario where you could count the action on your fingers. If you are at a job interview, you might use it to talk about how many times you led a project. If you are ordering food, you might use it to say how many times you've tried a specific dish.

Do not use 回 for duration. If you want to say you studied for three hours, use 時間 (jikan), not 回. 回 is for the *event*, not the *length* of time. Also, avoid using it for the very first time you do something if you want to sound natural. While 一回目 (ikkaime) means "the first time in a sequence," usually people just say 初めて (hajimete) for a brand new experience. It is like the difference between saying "This is my first time eating natto" and "This is the first occurrence of my natto-eating habit." One sounds like a human, the other sounds like a spreadsheet. Finally, do not use it for floor levels in a building. That uses 階 (kai), which sounds the same but uses a different kanji. Yes, Japanese loves to keep things spicy with homophones!

The biggest trap is the pronunciation of 一回 (ikkai). Many people say ichikai because they learned ichi is one. If you say ichikai, people will understand you, but it sounds a bit clunky. Think of the small っ as a tiny speed bump. Another mistake is forgetting the particle に (ni) when talking about frequency. If you say "Twice a week," it must be 一週間に二回 (isshuukan ni nikai). Without the に, it just sounds like "One week, two times," which is a bit robotic. Also, be careful with 何回 (nankai) vs 何回も (nankai mo). 何回 is a question ("How many times?"), but 何回も means "Many times!" (with emphasis). Don't accidentally ask a question when you are trying to brag about your high score!

You might encounter 度 (do) alongside 回. They are like cousins. 回 is very physical and literal. Use it for things you can physically repeat, like jumping or clicking a button. 度 is a bit more abstract or formal. You use 度 for "occasions" or "degrees." For example, "One more time" is usually もう一度 (mou ichido) in polite speech, but もう一回 (mou ikkai) in casual chat. Think of 回 as a spinning wheel (the kanji even looks like one!) and 度 as a point on a scale. For most daily actions, 回 is your safest bet. If you are counting how many times you've been married or how many times you've failed an exam, 度 adds a bit of weight and drama. For counting push-ups, stick to 回 unless you want to sound like a poet at the gym.