は vs が: The Real Difference (with Plenty of Examples)
Why this pair is hard
は and が are the first particles you learn and the ones learners second-guess for years — not because the rule is complicated, but because English doesn't mark the difference at all. Both can land on the word that English would call the "subject," so the trick is learning to feel what each one is doing rather than translating.
The good news: a handful of clear patterns cover the vast majority of cases. Let's build them up.
は = the topic ("as for…")
は lifts something up and says "here's what I'm going to talk about." A useful mental translation is "as for X." Everything after it is a comment about that topic.
ぼくはヤッタンです。
ぼくは ヤッタンです。
I'm Yattan. (As for me, [I]'m Yattan.)
ヤッタン is the topic — we're talking about himself.
今日は天気がいいですね。
きょうは てんきが いいですね。
The weather's nice today, isn't it?
今日 (today) is the topic; notice いい天気 itself is marked with が.
ヤッタンはお酒は飲みません。
ヤッタンは おさけは のみません。
Yattan doesn't drink alcohol. (As for alcohol, he doesn't drink it.)
Because は sets a topic, it often carries a sense of contrast: お酒は飲みません can hint "alcohol, I don't drink (but other things, maybe)."
が = the subject (who/what, often new)
が points at the actual doer or the thing that exists, and it often introduces new information — the answer to an unspoken "who?" or "what?"
あっ、モチが来た。
あっ、モチが きた。
Oh, Mochi's here.
Mochi is new information — you're reporting who just showed up.
誰がこのケーキを作りましたか。
だれが この ケーキを つくりましたか。
Who made this cake?
Question words like 誰 (who) always take が, never は.
That last point is a reliable rule: question words (誰, 何, どれ…) take が, and so does the answer to them. "田中さんが作りました" ("Tanaka made it") singles out Tanaka.
The "known vs. new" rule
Here's the idea that ties it together. Compare:
| Form | Core idea | Example |
|---|---|---|
| 猫が好きです | が singles out the subject of liking / new info | (It's) cats (that) I like / Cats are liked |
| 猫は好きです | は sets 'cats' as the topic, often contrastive | As for cats, I like them (dogs, maybe not) |
A classic illustration is the "Once upon a time" pattern. A story opens with が to introduce someone new, then switches to は once they're the established topic:
昔、一匹の子犬がいました。その子犬はヤッタンという名前でした。
むかし、いっぴきの こいぬが いました。その こいぬは ヤッタンと いう なまえ でした。
Long ago, there was a puppy. The puppy was named Yattan.
First mention → が (new). Second mention → は (now the topic).
Three quick rules of thumb
- Question words use が — and so do their answers. 何が好きですか → りんごが好きです.
- New on the scene → が; already on stage → は. Introduce with が, continue with は.
- Whole-sentence comment → は; "it's specifically X" → が. 私は学生です (about me) vs だれが学生？ → 私が学生です (it's me).
A note on 〜は〜が
Many natural sentences use both: a topic with は, and an inner subject with が.
象は鼻が長い。
ぞうは はなが ながい。
Elephants have long trunks. (As for elephants, the nose is long.)
象 = topic (は); 鼻 = subject of 長い (が). A core JLPT pattern.
If you can read 象は鼻が長い and feel why each particle is where it is, you've basically got it.
Common mistakes
- Using は in a question with a question word. It's 誰が来ますか, never 誰は来ますか.
- Overusing が for ordinary statements about yourself. Introducing yourself is 私は…, not 私が… (unless you're singling yourself out as the one).
- Forgetting は's contrast flavour. If you only mean "I drink coffee" neutrally, 私はコーヒーを飲みます is fine; just know は can imply "coffee (as opposed to other things)."
Quick recap
- は = topic, "as for…", known info, can contrast.
- が = subject, who/what, new info, answers "who?"
- Introduce with が, continue with は.
- Question words always take が.
Your turn
Choose は or が for each sentence.
＿＿＿に入れるのに最もよいものを選びなさい。
Which expression best fits the blank?
だれ＿＿＿来ましたか。
Frequently asked questions
Is it ever okay to use both は and が in one sentence?
Yes — very often. A topic takes は and an inner subject takes が: 象は鼻が長い ('as for elephants, the nose is long'). This は…が pattern is extremely common.
Why do question words like 誰 use が?
Because they ask for new, unknown information — exactly what が marks. The answer keeps が too: 誰が来た？ → 田中さんが来た.
Does は always mean contrast?
Not always, but it can. は sets a topic, and depending on context and stress it may imply 'X (as opposed to other things).' Tone and situation tell you whether the contrast is intended.
Quick test: 私は学生です or 私が学生です?
Use 私は学生です to simply say 'I'm a student.' Use 私が学生です only to single yourself out — e.g. answering 'who is the student?' ('I'm the one who is').
The patterns compared here
Full guide for each pattern in this comparison: