Overview
All four of these words mean “but / however,” yet you can’t swap them freely, because they sort along two axes at once. The first axis is position: でも and しかし are sentence-starters — they begin a brand-new sentence after a period. けど and けれども are clause-connectors — they sit at the end of the first clause and glue it to the second inside one sentence. The second axis is formality: でも and けど are casual; しかし and けれども are formal. Put those together and the whole group snaps into a tidy 2×2 grid — casual starter でも, formal starter しかし, casual connector けど, formal connector けれども. The shorthand for students: starts a sentence or joins a clause? and casual or formal? — answer both and only one word fits. They confuse learners because English “but” covers all four jobs with a single word, so beginners reach for whichever they learned first and use it everywhere. The sections below fix each word to its slot. The entries lead with a simple example, then a funny one. (They’re presented as two starters first, then two connectors, so the grammar lines up.)
でも — “but (casual, starts a sentence)”
Explanation
でも begins a new sentence and pushes back against the sentence before it, in a casual, conversational tone. You finish one thought with a period, then open the next with でも: 今日は日曜日です。でも、仕事があります (“Today is Sunday. But I have work”). It’s the everyday spoken “but” — the one you’ll hear most in normal conversation. Because it stands at the head of its own sentence, it never attaches to the previous clause; it waits for the period and then answers back. Think of it as the friendly, informal counterpart of the stiffer しかし.
Grammatically, でも is a conjunction that begins a sentence, almost always followed by a comma: 〜。でも、〜。 It does not connect two clauses the way けど does — you cannot glue clauses with it. One caution worth flagging early: the string でも has other, unrelated jobs in Japanese (お茶でも飲む “have some tea or something,” 子供でも分かる “even a child understands”). Those are different grammar points; here we mean only the sentence-starting “but.” When でも opens a sentence and contradicts the one before it, it’s this contrastive conjunction.
The register is casual and spoken, occasionally neutral in light writing. The teaching anchor is the casual sentence-starter: でも kicks off a new sentence to object to the last one, informally. It differs from しかし, which does the same job formally, and from けど/けれども, which contradict inside one sentence rather than starting a new one. If the student is speaking casually and wants to begin a fresh “but…” sentence, でも is the fit.
Examples
このレストランは安いです。でも、あまりおいしくないです。 — This restaurant is cheap. But it’s not very tasty.
🍫 私は今、ダイエットをしています。でも、チョコレートを食べました。でも、明日からまたがんばります。でも、明日も同じことを言います。 — Right now I’m on a diet. But I ate chocolate. But I’ll try hard again from tomorrow. But tomorrow I’ll say the same thing.
Common mistake
Don’t use でも to join two clauses inside one sentence — that’s けど’s job. ✗ 安いでも、おいしくないです is wrong. You must either start a new sentence (安いです。でも、おいしくないです。) or switch to a connector (安いけど、おいしくないです). でも needs a period in front of it; it opens a sentence, it doesn’t stitch one together.
しかし — “however (formal, starts a sentence)”
Explanation
しかし does exactly what でも does — begins a new sentence to contradict the previous one — but in a formal, written register. It’s the “however” of essays, news articles, speeches, and serious writing: 実験は失敗した。しかし、大切なことが分かった (“The experiment failed. However, we learned something important”). It sits at the head of its sentence just like でも, but it sounds markedly more serious and objective, so it belongs in contexts where でも would feel too chatty.
Grammatically, しかし is a sentence-initial conjunction, typically followed by a comma: 〜。しかし、〜。 Like でも, it never attaches to the preceding clause and never connects clauses within a sentence; it always starts a fresh one. Its position is identical to でも’s — the only thing that changes between them is the formality level. That parallel is worth remembering: でも and しかし are the same grammatical shape (sentence-starters), just tuned to different registers.
The register is formal and written (or spoken in formal settings like speeches and presentations). The teaching anchor is the formal sentence-starter: しかし opens a new sentence to object, seriously. It differs from でも only in formality, and from the connectors けど/けれども in position. If the student is writing an essay or speaking formally, しかし is the fit.
Examples
たくさん練習しました。しかし、試合に負けました。 — I practiced a lot. However, I lost the match.
⏰ 私は今日、朝五時に起きました。しかし、それは日曜日でした。 — Today I woke up at five in the morning. However, it was Sunday.
Common mistake
Don’t drop しかし into casual chat with friends — it sounds like you’re reading the news aloud. ✗ Saying パーティーに行きたい。しかし、お金がない to a close friend is too stiff; a friend would say …でも、お金がない. Keep しかし for writing and formal speech. Also, like でも, it starts a sentence — don’t try to use it as a clause connector (✗ 高いしかし買う).
けど — “but / although (casual, connects clauses)”
Explanation
けど joins two clauses inside a single sentence, casually: A けど B means “A, but B.” Instead of stopping and starting a new sentence, you attach けど to the end of the first clause and keep going: このかばんは高いけど、買います (“This bag is expensive, but I’ll buy it”). It’s the everyday spoken connector, and it often softens the whole statement, which is why casual Japanese leans on it so heavily. けど is actually the clipped, casual form of けれども — same meaning, shorter and more relaxed.
Grammatically, けど attaches to the end of a clause and can follow either a plain or a polite form, which makes it flexible. After a verb: 行くけど / 行きますけど. After an い-adjective: 高いけど / 高いですけど. After a な-adjective or noun, you keep だ or です: 静かだけど / 静かですけど, 学生だけど / 学生ですけど. Notice the difference from でも: でも needs a period before it, but けど lives inside the sentence, hanging off the first clause with no period. This is the core grammatical split between starters and connectors.
The register is casual and spoken. The teaching anchor is the casual clause-connector: けど ties “A, but B” together in one breath, informally. It differs from けれども, which does the same job more formally, and from でも/しかし, which start separate sentences. If the student is speaking casually and wants to link a contrast within one sentence, けど is the fit.
Examples
この映画は長いけど、おもしろいです。 — This movie is long, but it’s interesting.
🐶 私の犬は小さいけど、とても元気です。私は大きいけど、いつもねむいです。 — My dog is small, but it’s very energetic. I’m big, but I’m always sleepy.
Common mistake
Don’t put a period before けど as if it were でも — けど must cling to the first clause. ✗ 高いです。けど、買います treats it like a sentence-starter, which reads awkwardly; write 高いですけど、買います (one sentence) instead. If you truly want a period and a fresh sentence, use でも: 高いです。でも、買います。
けれども — “but / although (formal, connects clauses)”
Explanation
けれども connects two clauses inside one sentence just like けど, but in a more formal, polite register. 日本語はむずかしいですけれども、たのしいです (“Japanese is difficult, but it’s fun”) sounds politer and more composed than the same sentence with けど. It’s the connector of choice in polite conversation, careful writing, and situations where けど would feel too casual. The family runs from formal to casual as it shortens: けれども → けれど → けど (and the variant けども), all meaning the same “but,” with けれども the most formal and けど the most relaxed.
Grammatically, けれども behaves exactly like けど — it attaches to the end of a clause, after either a plain or polite form: 行きますけれども, 高いけれども, 学生ですけれども. The build is identical; only the length (and therefore the politeness) changes. So the two connectors, けど and けれども, are the same grammar at two formality levels, precisely mirroring how でも and しかし are the same starter at two formality levels.
The register is formal-to-polite, common in both writing and courteous speech. The teaching anchor is the formal clause-connector: けれども links “A, but B” in one sentence, politely. It differs from けど only in formality, and from でも/しかし in position. If the student is being polite or writing carefully and wants an in-sentence contrast, けれども is the fit.
Examples
たくさん食べましたけれども、まだおなかがすいています。 — I ate a lot, but I’m still hungry.
📚 私は毎日勉強しますけれども、テストはいつも0点です。先生は「がんばりましたね」と言いますけれども、先生の目はわらっていません。 — I study every day, but my tests are always zero points. The teacher says “You worked hard, didn’t you,” but the teacher’s eyes aren’t smiling.
Common mistake
Don’t mix formality levels inside one sentence — if you open politely, close politely. ✗ 勉強しますけれども、ねむいだ mismatches the polite 勉強します with the plain ねむいだ; make it 勉強しますけれども、ねむいです. And don’t reach for けれども in super-casual chat, where it can sound overly formal; there, けど is the natural choice.
How to choose
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