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N4Lesson notes · Oct 6, 2026

By the way in Japanese: ところで (tokorode) vs ちなみに (chinamini) and when to use each

"By the way" is two different words in Japanese: ところで when you change the subject, and ちなみに when you add a related detail to the current one.

English uses one phrase for both jobs. Japanese splits them, and that split is the reason a perfectly polite learner can sound abrupt. This article gives you the pair, the three or four casual and formal alternatives around them, and the traps that show up again and again in lessons.

The basics

What is "by the way" in Japanese?

The two main answers are ところで (tokorode) and ちなみに (chinamini). They are not interchangeable, and picking the right one is the whole skill.

  • ところで — "by the way" in the sense of "anyway, switching topics." The new topic has nothing to do with what you were just saying.
  • ちなみに — "by the way" in the sense of "incidentally, for the record." The new information is attached to the current topic.

ところで、明日あしたの会議かいぎは何時なんじでしたっけ。 — By the way, what time is tomorrow's meeting again? (polite-neutral, a clean change of topic) ちなみに、その店みせは日曜にちようも開ひらいています。 — Incidentally, that shop is open on Sundays too. (neutral, extra detail about the shop you were already discussing)

A quick test: ask whether your sentence is still about the thing you were just talking about. If it adds a detail to that same topic, use ちなみに. If it points to something unrelated, use ところで.

Where does it go in the sentence?

At the very front. Japanese has no "by the way" that trails at the end of a sentence, so the English habit of "I like it, by the way" has to be rebuilt as a new sentence that starts with the marker.

ちなみに、私わたしはコーヒーより紅茶こうちゃが好すきです。 — By the way, I like tea more than coffee. (neutral, marker first, comma after it) ところで、最近さいきんどうですか。 — By the way, how have you been lately? (polite, steering the talk to a new subject)

A small comma (、) after the marker is normal in writing and shows up as a tiny pause in speech.

How is ところで different from the word ところ?

ところ means "place" or "point" in many phrases, and learners sometimes hear "where" inside ところで and expect it to be about location. In this use it is a fixed conjunction, a topic-switcher, and the "place" meaning is not active. You do not need to analyse it. Treat ところで as one block that means "now, about something else."

It does have a second life in the middle of a sentence: 〜たところで, as in "even if you do it, it won't matter." That is a different grammar point. When ところで opens a sentence by itself, it is only a topic-change signal.

Beyond the basics

What do you say for "oh, that reminds me"?

Use そういえば. It is the "wait, I just remembered" version: something said earlier triggered a thought, and you pull it up out loud. Since we already cover it in depth in と言いえば vs そういえば, here is only the short version: ところで changes the topic on purpose, そういえば changes it because your memory just fired.

そういえば、あの映画えいが、もう見みました? — Oh, that reminds me, did you already see that movie? (neutral, a thought surfacing mid-conversation)

What is the spoken, "oh, by the way" version?

あ、そうだ is the exclamation you make when a thought lands. It is the spoken partner of そういえば, a little more physical and immediate. Often it is followed by a request or a reminder.

あ、そうだ、明日あした傘かさを持もってきてね。 — Oh, by the way, bring an umbrella tomorrow. (casual, sudden reminder)

Anime uses this constantly because it is a cheap, natural way to let a character break the rhythm of a scene.

How do you change the subject more casually?

Say 話はなしは変かわるけど (hanashi wa kawaru kedo, "the topic is changing, but...") or the even more relaxed 話はなし変かわるんだけど with the は dropped. These openers announce the switch, which makes the new topic feel less abrupt than a bare ところで.

話はなしは変かわるけど、週末しゅうまつひま? — Changing the subject, are you free this weekend? (casual, friends) 話はなし変かわるんだけど、ちょっと相談そうだんしていい? — Speaking of something else, can I ask your advice? (very casual, softening the request with んだけど)

Compare how んだけど softens this: the same mechanism is explained in the explanatory んです.

What is the formal, written "by the way"?

余談よだんですが (yodan desu ga, "a digression, but...") belongs to speeches, presentations, and writing. It tells the listener "this is a side note, feel free to treat it as a footnote."

余談よだんですが、この制度せいどは去年きょねんから変かわりました。 — As a side note, this system changed from last year. (formal, speech or writing)

Closely related is ついでに, which means "while I'm at it" and attaches an extra action rather than a topic, so it is a neighbour, not a synonym.

What about the old-fashioned version?

それはそうと (sore wa sou to) is "that aside" or "be that as it may." Real people use it less today, but it fits characters who are older, composed, or trying to steer a discussion back to business. In anime, a calm adult saying それはそうと is usually the sign that the previous subject has been dealt with and the real agenda is next.

How do these actually sound in anime?

You will hear all of these in short, punchy forms, and a few details help your ear:

  • ところでさ — a casual friend pivoting. The さ is a conversational pause.
  • ちなみに俺おれは反対はんたいだ — a character giving a side opinion for the record, not asking for a vote.
  • そういえばあいつどこ行いった? — a missing character is suddenly remembered mid-scene.
  • 話はなしは変かわるが — a serious character with a flat, formal tone shifting to a heavier subject.

ちなみに、俺おれは反対はんたいだ。 — For the record, I'm against it. (masculine casual, an aside) そういえば、あいつどこ行いった? — Come to think of it, where did that guy go? (casual, thought surfacing) 話はなしは変かわるが、例れいの件けんはどうなった。 — Changing the subject, what happened with that matter? (blunt, an authoritative character)

Notice that every one of these starts with the marker. Even in rapid anime dialogue, the marker comes first and the question or statement follows.

Do ちなみに and ところで change in real conversation?

Both usually survive, but their length and tone shift. ちなみに is common in chat and email as well as speech, often written with a trailing "ですが" in business messages. ところで is used spoken far more than in formal writing, where 余談よだんですが or a paragraph break often does the job.

Common mistakes

  • Using ところで for a side detail. If you are still on the same subject, ところで makes it sound like you stopped listening. Use ちなみに instead. ちなみに also works as a quiet way to add a fact about yourself without hijacking the conversation.
  • Putting "by the way" at the end. 私わたしは紅茶こうちゃが好すきです、ちなみに is not natural. Start a fresh sentence with ちなみに.
  • Thinking ちなみに is only written Japanese. It is very common in speech, chat, and email. It is not stiff.
  • Hearing "where" in ところで. The ところ here is not about place. Treat the whole word as a topic switch.
  • Using ところで to ask something truly urgent. If the question is serious, ところで can sound dismissive. A softer opener like 「話はなしは変かわるけど」 or 「あの、ちょっといいですか」 is safer.
  • Over-using one marker. Learners often settle on ところで and use it everywhere. Native speakers rotate between ちなみに, そういえば, and あ、そうだ depending on whether the thought is related, remembered, or sudden. If you want a sense of how natural speech fills its gaps, see Japanese filler words.

Which one fits which situation?

Marker Relation to previous talk Politeness Example
ところで Unrelated, a new topic Neutral to polite ところで、最近忙さいきんいそがしいですか。
ちなみに Related, extra detail Neutral, works in writing ちなみに、駅えきから徒歩とほ5分ふんです。
そういえば Triggered by a memory Casual to neutral そういえば、鍵かぎは?
あ、そうだ Sudden thought Casual, spoken あ、そうだ、お土産みやげあるよ。
話はなしは変かわるけど Unrelated, announced Casual 話はなしは変かわるけど、週末しゅうまつどうする?
余談よだんですが Related but off to the side Formal 余談よだんですが、創業そうぎょうは昭和しょうわです。

Use the middle column first. If your information is attached to the current subject, pick ちなみに or 余談よだんですが. If you are leaving the subject, pick ところで or 話はなしは変かわるけど. If it just popped into your head, pick そういえば or あ、そうだ.

If you are unsure which register to speak in with a particular person, our guide on keigo vs casual Japanese covers when to switch.

Practice

Build each answer before opening it. Questions 1 and 2 are a pair: the same shape of sentence, but the marker has to change.

1. You are talking about a restaurant you both liked. You want to add "it's closed on Mondays." Which marker do you start with: ところで or ちなみに?

Show answer

ちなみに — the information is attached to the restaurant you were already discussing, so it is a side note, not a new topic. ちなみに、月曜げつようは休やすみです。

2. You were talking about the restaurant and now you want to ask what time the meeting starts tomorrow. Which marker?

Show answer

ところで — the meeting has nothing to do with the restaurant, so you are changing the topic. ところで、明日あしたの会議かいぎは何時なんじですか。

3. What is wrong with 私わたしは紅茶こうちゃが好すきです、ちなみに?

Show answer

The marker is at the end. Japanese puts "by the way" at the front: ちなみに、私わたしは紅茶こうちゃが好すきです。

4. Which marker fits "oh, that reminds me, did you lock the door?"

Show answer

そういえば — something earlier jogged your memory. そういえば、鍵かぎはかけましたか。

5. A friend is leaving and you suddenly remember to mention the umbrella. Which casual spoken phrase fits?

Show answer

あ、そうだ — the spoken "oh!" of a thought landing. あ、そうだ、傘かさを持もっていってね。

6. You want to announce a casual subject change to a friend. Give a natural opener.

Show answer

話はなしは変かわるけど (or 話はなし変かわるんだけど) — it announces the switch, which softens it for friends.

7. You are giving a presentation and want to add a side note about the company history. Which formal opener?

Show answer

余談よだんですが — "a digression, but...", the speech and writing register for side notes.

8. True or false: ちなみに is only used in written Japanese.

Show answer

False. It is common in speech, chat, and email. It is neutral, not stiff.

9. An older, composed anime character says それはそうと before turning to the main business. What does it signal?

Show answer

The previous subject is closed and the real agenda starts. それはそうと is "that aside", slightly old-fashioned, and fits a calm adult voice.

10. Is the ところ in ところで about place?

Show answer

No. In this use ところで is a fixed topic-switch word. The "place" meaning is not active.

Changing the subject smoothly is easier with a partner, so chat for a while in a trial lesson and slip in ところで, ちなみに or そういえば where each one belongs.

FAQ

Is ところで rude if I use it to change the subject at work? No, it is standard and polite enough. In a very formal setting you can soften it by pausing first, or choose 話はなしは変かわりますが ("the subject changes, but..."), which announces the shift before making it.

Can I use ちなみに when I want to ask a question? Yes. ちなみに works for a related question too, as in ちなみに、お名前なまえは何なんですか ("incidentally, what is your name?"). It sounds natural when the question relates to what you were already discussing.

What is the difference between ちなみに and そういえば? ちなみに adds information to the current subject, while そういえば appears because the conversation reminded you of something. The first is deliberate and tidy, the second is spontaneous. For more, see our article on と言いえば and そういえば.

Which is more casual, ところで or 話はなしは変かわるけど? 話はなしは変かわるけど is more casual and friendlier, because it announces the change before making it. ところで is neutral and can feel a bit sudden without a warm tone.

Do I need a comma after ちなみに and ところで? In writing, a comma (、) is standard. In speech, it becomes a tiny pause. Casual speech can run straight through: ちなみに俺おれは反対はんたいだ.

Is あ、そうだ the same as そういえば? Close, but not identical. そういえば links back to what was just said. あ、そうだ is an exclamation of a thought hitting you, and it can be about anything, not only the current subject.

Vocabulary from this article

Tap the block to select all of it, then copy. In Anki: File → Import, note type Basic, separator Tab, and the two columns land in Front / Back.

ところで	ところで — by the way, now then (topic change)
ちなみに	ちなみに — incidentally, for the record
そういえば	そういえば — come to think of it
あ、そうだ	あ、そうだ — oh, that's right, by the way
話は変わるけど	はなしはかわるけど — changing the subject, but
余談	よだん — digression, side note
それはそうと	それはそうと — that aside
ついでに	ついでに — while I'm at it
会議	かいぎ — meeting
傘	かさ — umbrella
反対	はんたい — opposition

I'm Yuuki, a Japanese teacher based in Tokyo. I've taught on italki as a Top 1% teacher and watched over 1,500 anime, so most of the example sentences on this blog come from lines I've actually heard students ask about — including this one, which comes up in nearly every beginner's first few lessons. For practice with feedback, Book a trial lesson · $13, or work through Japanese practice exercises first.

Sources: the author's own lessons and standard reference grammars.

More drills like the ones above, plus a timed JLPT-style mock test: Practice · N4 · Read something at this level: JLPT N4 stories with audio

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